Loading...
1997-1343 G/H/T Street Address I a10b BIbS Category Serial # J3Y3 9 Name Description Plan cle. # Year ~/ , ~f v ~,,,,.~tffd"rIlPr~/II(Jn9o&/ftOoreL -~~- -'~C;;:'?f > ti< , I "-""'''''' "",,,,, ,"oo fn"""""""',,,' '"'''''' 1'1 Cnmult,'''" 13 f3 ~ I I I I I I I I I I I I I I I I I j-::<.'\ !~: 1;..) It ! "\ c~ 1 n 1 L~ L}, L', APR 03 1997 ENCt,'\JE~~,;1~NC SE:F~iJlC~S CiTY OF Ej\]Cl~j\Tj-\S GEOTECHNICAL EVALUATION PROPOSED NEW SINGLE-FAMILY RESIDENCE 405 LIVERPOOL DRIVE CARDIFF-BY-THE SEA, CALIFORNIA PREPARED FOR: Mr. Steve Beck 405 Liverpool Drive Cardiff-by-the-Sea, California 92007 PREPARED BY: Ninyo & Moore Geotechnical and Environmental Sciences Consultants 10225 Barnes Canyon Road, Suite A-Il2 San Diego, California 92121 March 31, 1997 Project No. 103354-01 1022':) Rirnes C:lnyon Road . Suite A-I 12 . San Oie9o, California 92121 Phone (6 19) 4S7-040() . Fax (619) S58- 1236 9272Jf:'ronImo/~()ad a Suite 1)3A ~ Irvine, Cl!ifornin 97718 . Phone(7J4)47JS444 . Fi.'lX(714)4/2-S4'15 J 55 West Hmpirality Ldrle . Suite 165 . San Bernardino, California 9)408 . Phone (909) 383-8777 . Fax (909) .183-8776 :~~-rffir?I~J7)/IfJn90&"'~~~~:.",...=:.~:.=.'~VJ== March 31, 1997 I Project No. 103354-01 I I I I I I I I I I I I I I I I Mr. Steve Beck 405 Liverpool Drive Cardiff-by-the-Sea, California 92007 Subject: Geotechnical Evaluation Proposed New Single-Family Residence 405 Liverpool Drive Cardiff-by-the-Sea, California 92007 Dear Mr. Beck: In accordance with your authorization, we have performed a geotechnical evaluation for the sub- ject project that will be located at 405 Liverpool Drive in Cardiff-by-the-Sea, California. The attached report presents the results of our subsurface exploration and laboratory testing, and our recommendations regarding the geotechnical aspects of the proposed construction. We appreciate the opportunity to be of service on this project. If you have any questions or com- ments regarding our report, please contact the undersigned. _._.." \'"D G~ "- ...~...\..- '1...:0 "- ,S' ,;<\~" ......~ ,,' ~,'~ (;' r\c.>o l_. I '). ~ {~'" --::"l,-:.~}\ : a:: E~)~L"'/Y;) <1>.... Gc~ J~'~tJ ,''''' . . (l ~"",,,, ,. ~ j <:OFc^~<C>' Randal L. Irwin, RG 4582, CEG 1521 Chief Engineering Geologist Respectfully submitted, NINYO & MOORE U~ Erik Olsen, RCE 42727, GE 2218 Senior Project Engineer ~~ Avram Ninyo, RCE 2 8, GE 642 Principal Engineer BABIEO/RI/ AN/atf Distribution: (3) Addressee 10225 Bdrncs C-myon Roae! . Suite AI 12 . S;]n Diego. lornla 92 J) 1 . ('hone (619) 4.')7-0400 . FdX (619) S58-1236 9277Jcronirn(JRo~ld . Suite 123A . Irvine, California 927J8 . Phonc(7J4)472-5444 . F;:Jx(114)472-S445 15S West HOSPltc1Jity Lane . Suite 165 . San Bernc1rdino, Californid 92408 . Phone (909) 383-8177 . FcJX (909) 383-8776 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Liverpool Drive March 31, 1997 Project No. 103354-01 TABLE OF CONTENTS Pal!e 1. INTRODUCTION ..... ...... .... ..... ....... ...... ..... ...... ...... ... .... ... .... .... .... ....... .... .... .... ..... ........ ..... ..... I 2. SCOPE OF SERVICES.. ..... ............ ..... ...... ..... ...... .... .... ... .... ... ........... ..... .... .... ..... .... .... ........... 1 3. SITE DESCRIPTION .... .... ..... ....... ........... ..... ..... ..... .... ....... ... ..... ..... ...... .... .... ..... ..... ....... ........ 1 4. PROPOSED CONSTRUCTION... ..... ...... ..... ........... .... ... ....... .... ...... ..... ..... .... ..... ........... ...... ... 2 5. SUBSURFACE EXPLORATION AND LABORATORY TESTING....................................... 3 6. GEOLOGY AND SUBSURFACE CONDITIONS..................................................................3 6.1. Geologic Setting.... ..... ...... ...... ...... ..... ..... .... ..... ....... ....... ..... ..... ...... .... .... ..... ... .... .... ........ 3 6.2. Site Geology.... ..... .... ...... ..... ...... ...... ..... ...... ... .... .... ... ... .... ....... ..... .... .... ...... ... ....... ...... ... 4 ~.1.~.......................................................................................................................4 6.2.2. Terrace Deposits.. ...... ..... ...... ..... ...... ........ ... .... ... .... ...... ...... .... .... ..... .... .... ... ...... .... 4 6.3. Groundwater ....... .... ...... ..... ...... ..... ...... ..... ..... .... ... .... .... ... ...... ...... ........ .... .... .... .... ..... .....4 7. FAULTING AND SEISMICITY. ..... ...... ...... ..... ..... .... ... .... ....... ...... ..... ..... ........ .... .... .... .... .......4 7.1. Ground Surface Rupture... ...... ...... ..... ...... ..... ....... ....... .... ..... ...... ..... ....... ..... .... .... ... ........ 6 7.2. Liquefaction and Seismically Induced Settlement ...........................................................6 8. CONCLUSIONS ..... ....... .... ..... ...... ..... ...... ........... .... ....... .... ... .... ...... ...... .... .... .... .... .... .... ..... .... 6 9. RECOMMENDATIONS. .... ..... ...... ..... ...... ..... ..... ..... .... ... ... .... .... ..... ....... ... ......... .... ............ .....7 9.1. Earthwork ...... ...... .... ..... ...... ...... ...... .... ...... ........ .... ... .... ... ...... ....... ... ......... ... .... .... ..... .....7 9.1.1. Excavations......................................................................................................... 7 9.1.2. Fill Placement and Compaction ............................................................................8 9.1.3. Import Fill Material...... ..... ..... ...... ..... ........... .... ... .... ...... ..... ........ ..... .... .... ......... ...8 9.2. Foundations. ....... .... ..... ..... ...... ..... ..... ...... ..... .... ... .... .... ... .... ...... ..... .... .... ..... .... ... .... ..... ....8 9.2.1. Bearing Capacity... ..... ...... ..... ...... ..... ........ .... ... ........ ..... ...... .... .... .... .... ... ..... .... .....8 9.2.2. Lateral Earth Pressures .... ...... ...... ..... ..... ... ....... .... .......... ..... .... .... .... .... .... ........ .....9 9.2.3. Floor Slabs .. .... ..... ..... ...... ...... .... ...... ........ .... .... ... .... ..... ...... .... ... ..... .... ........ .... ......9 9.2.4. Settlement... .... ..... ...... ..... ...... ..... ..... ..... ... .... ....... ... ..... ....... ....... ..... .... .... ... .... ..... 10 9.3. Retaining Walls .... ..... .... ..... ...... ...... .... ...... ........ .... ....... .... ..... ..... ..... .... .... .... ........ .... ..... 10 9.4. Flatwork.. ...... ...... ..... .... ...... ..... .... ...... ...... .... ..... ... .... ... ... ..... ...... ........ ..... .... .... .... ... ....... 11 9.5. Moisture Conditioning and Concrete Placement...........................................................l1 9.6. Soil Corrosivity .. ..... .... ..... ..... ...... ..... .... ....... .... ... .... ... .... ..... ..... ..... .... .... .... .... .... .... .... ... 11 9.7. Concrete Placement ........ ....... .... ...... ..... ..... ..... ... .... .... ... ... ....... ..... .... .... ..... ... .... .... ..... ... 12 9.8. Site Drainage.... ..... .... ..... ..... ...... ...... .... ...... .... .... .... ... ....... ..... ........... .... .... .... ........ ... ..... 13 9.9. Construction and Observation Testing .........................................................................13 10. LIMITATIONS....... ..... .... .... ..... ..... ........ ... ...... .... ..... ....... ... .... ..... ..... ..... .... .... .... .... ....... ....... 14 11. SELECTED REFERENCES .... ..... ....... .... ...... ..... .... .... .......... ..... ..... ..... ... ..... ..... '" .... ... ..... ... 15 JJ54-0IR,DOC l(in9o&l(t.oon I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Liverpool Drive March 31, 1997 Project No. 103354-01 Tables TABLE 1 - Seismic Parameters For Maximum Probable Earthquakes TABLE 2 - Continuous Foundation Dimensions llIustrations Figure 1 - Site Location Map Figure 2 - Site Plan Figure 3 - Fault Location Map Figure 4 - Retaining Wall Drain Detail Appendices Appendix A - Appendix B - Appendix C - Test Pit Logs Laboratory Testing Typical Earthwork Guidelines 3)S4-(IIR.DOC ii /(in9o&/ftoon I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Liverpool Drive March 31, 1997 Project No. 103354-01 1. INTRODUCTION This report presents the results of our geotechnical evaluation for the proposed single-family resi- dence that will be located at 405 Liverpool Drive in the Cardiff-by-the-Sea community of Encinitas, California. The purpose of this evaluation was to provide design and earthwork rec- ommendations regarding the geotechnical aspects of the proposed construction. This report presents the results of our subsurface exploration and laboratory testing, our conclusions regard- ing geotechnical conditions of the project site, and our recommendations for the design and construction of this project. 2. SCOPE OF SERVICES Ninyo & Moore's scope of services for this phase of the evaluation included the following: . Review of preliminary project plans, available geologic maps, reports, and stereoscopic aerial photographs pertaining to the site vicinity. . Subsurface exploration consisting of manually excavating two test pits for the purposes of obtaining representative soil samples and observing subsurface conditions. The test pits were excavated to depths of approximately 3.0 and 5.5 feet, and were logged by a geologist from our firm. . Laboratory analysis consisting of in-situ dry density and moisture content, direct shear, re- molded shear, maximum dry density and corrosivity tests, including chloride and sulfate content, pH and minimum resistivity. . Compilation and analysis of the data obtained. . Preparation of this report presenting the results of our evaluation, and our conclusions and recommendations regarding the site earthwork, retaining walls and foundations. 3. SITE DESCRIPTION The project site, located at 405 Liverpool Drive, Cardiff-by-the-Sea, California, consists of a rec- tangular-shaped, approximately 5,000-square-foot lot located southeast of the intersection of Liverpool Drive and Cambridge Avenue in the Cardiff-by-the-Sea community of Encinitas, Cali- fornia (Figure I, Site Location Map). The lot currently supports a single-family, single-story, 33S4-0IROOC /(ln90&/V\OOf'e 1 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Liverpool Drive March 31,1997 Project No. 103354-01 wood frame residence which overlies a garage. The existing structure will be removed to provide space for the new residence. The residence fronts Liverpool Drive, which borders the site on the north, is bordered on the west by Cambridge Avenue, on the east by an unpaved alley way and to the south by similar lots supporting single-family residences. The lot is located on westerly- descending hillside terrain. The lot slopes approximately 10 percent westerly with elevations across the site ranging from approximately 184 feet mean seal level (MSL) at the east to approxi- mately 171 feet mean sea level (MSL) at the west. No grading plans or soils reports for the construction of the existing residence were available for review, consequently previous grading performed at the site is unknown. Based on observations made during our investigation, as well as review of available topographic maps, it appears that the existing residence is situated on a building pad created generally by cutting on the west portion of the lot (for the garage). The residence is founded on perimeter and isolated spread footings sup- porting raised-wood floors. Based on observations from the sub-floor crawl space, the foundations appear to be constructed on sloping terrain comprised of native soil. The eastern por- tion of the lot, at the rear of the existing residence, is approximately 4 to 5 feet higher in elevation with a retaining wall located approximately 5 to 7 feet east of the residence. This area was previ- ously used for parking. Grading for the east portion of the lot may have involved placement of some fill soil. 4. PROPOSED CONSTRUCTION A new, two-story, single-family residence will be constructed at the western and central portions of the lot. The residence will be founded on continuous perimeter and interior spread footings supporting a structural floor. The garage will be constructed underlying the western portion of the residence with a slab-on-grade floor at approximately one foot lower in elevation as the existing garage. A retaining wall is planned east of the residence, which will be created by cutting ap- proximately 5 feet into the eastern portions of the lot, generally east of the building footprint. 33S4-01R.OCX:: /fJn90&j~oo\"e 2 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Liverpool Drive March 31, 1997 Project No. 103354-01 5. SUBSURFACE EXPLORATION AND LABORATORY TESTING Our subsurface exploration was conducted on March 1, 1997, and consisted of the manual exca- vation of two exploratory test pits. Test pit TP-l was excavated to a depth of approximately 5.5 feet below ground surface (bgs), east of the existing residence at a location corresponding to the future building footprint. Test pit TP-2 was excavated to a depth of approximately 3.0 feet bgs, northwest of the existing residence in the area where footings for the proposed garage area will be constructed. The purpose of the test pits was to observe and sample the underlying earth materi- als. The test pits were logged and sampled by a geologist from this office and then backfilled with the cuttings generated from the excavation. The approximate test pit locations are shown on Fig- ure 2 and the test pit logs are presented in Appendix A. Relatively undisturbed and bulk samples were obtained from the test pits at selected intervals and were returned to our laboratory for analysis. The geotechnical testing included in-situ moisture and dry density, direct shear strength, remolded shear strength, maximum dry density, and corro- sivity tests. The results of the in-situ moisture and density testing are presented on the test pit logs in Appendix A. The remaining geotechnical test results are presented in Appendix B. 6. GEOLOGY AND SUBSURFACE CONDITIONS The following sections present our findings regarding geology and subsurface conditions. 6.1. Geologic Setting The subject site lies within a stretch of coastal hills that are contained within the coastal plain region of northern San Diego County, California. These coastal hills are characterized by nu- merous marine terraces of Pleistocene that were deposited on wave-cut platforms of the underlying Eocene bedrock. The terraces extend from inland areas of higher elevation ap- proximately one mile east of the site and descend generally west-southwest in a "stairstep" fashion down to the present day coastline. The subject property is situated on a portion of marine terrace referred to as the Quail Terrace (Eisenberg, 1983), which generally comprises the upper elevations of the coastal hills immediately north of the San Elijo Lagoon and west 3354-0IR.DOC 1(Jn90&~00\"8 3 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Liverpool Drive March 31, 1997 Project No. 103354-01 of Interstate 5 in the Cardiff area of Encinitas. This area is contained within the southeast portion of the United States Geological Survey Map Encinitas 7.5 minute quadrangle. 6.2. Site Geology The project site appears to be underlain by undocumented fill soils (reworked, on-site native soils) and marine terrace deposits of Pleistocene age. No evidence of bedding or faulting was observed in the test pits. Brief descriptions of geologic units observed within the site are de- scribed below. 6.2.1. Fill Fill soil was encountered in test pit TP-2 to a depth of approximately 0.4 feet. The fill generally consisted of medium brown, damp, medium dense silty sand. 6.2.2. Terrace Deposits Pleistocene terrace deposits were encountered in test pits TP-l and TP-2 at depths of less than 5 feet, underlying landscape gravel and fill soil, respectively. The terrace de- posits generally consisted of brown to brownish orange, damp to saturated, weakly to well cemented, slightly clayey and slightly silty sandstone. The terrace deposits are mod- erately friable on exposed surfaces. 6.3. Groundwater Perched groundwater was encountered at a depth of approximately 3.0 feet in test pit TP-2, excavated adjacent to the northwestern comer of the existing residence. The perched water zone likely fluctuates with seasonal rainfall, irrigation and other factors. 7. FAULTING AND SEISMICITY Based on our review of referenced geologic maps and stereoscopic aerial photographs, active or potentially active faults do not underlie the site. However, several faults in the southern California area may generate significant ground accelerations and associated ground shaking in the project 33S4-0IR_OOC IfJn9o&~oo\"e 4 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Liverpool Drive March 31, 1997 Project No. 103354-01 area. The approximate locations of major faults in the region with relation to the site are shown on Figure 3. The Rose Canyon fault zone, portions of which are considered active (displays evi- dence of movement during the last 11,000 years) by the State of California, is located offshore approximately 2 miles southwest of the site. The following table lists significant active faults that may affect the site, the estimated maximum probable seismic events which could occur on these faults, and the predicted ground accelerations at the site associated with these events. TABLE 1- SEISMIC PARAMETERS FOR MAXlMUM PROBABLE EARTHQUAKES Maximum Estimated Acceleration (g) Fault-ta-Site Probable Fault Distance Eartbquake Peak Repeatable (miles) Magnitude Horizontal Higb Bedrock1 GroundJ Agua B1anca-Coronado Bank 18 7.1 .26 .17 Newport Inglewood 36 6.5 .05 .05 Offshore Zone of Deformation 17 6.5 .14 .09 Rose Canyon 2 6.5 .45 .29 San Clemente 53 6.6 .04 .04 San Diego Trough 28 6.1 .05 .05 San Jacinto 52 7.1 .05 .05 San Miguel- Vallecitos 51 6.8 .05 .05 Whittier-Elsinore 28 7.2 .12 .12 Notes: I After Mualchin and Jones 1992; Wesnonsky, 1986; and Anderson et aI., 1989 'Mualchin and Jones, 1992 3Ploessel and Slosson, 1974 Based on the Maximum Probable Earthquake (MPE) magnitudes for faults listed in the preceding table and on the distance between the site and these faults, it is our opinion that the most signifi- cant MPE with respect to the project would be an earthquake of magnitude 6.5 occurring within the Rose Canyon fault zone. Based on attenuation curves published by Mualchin and Jones (1992), and on seismic research performed by Ploessel and Slosson (1974), the predicted peak horizontal bedrock acceleration produced at the site by the described MPE on the Rose Canyon fault would be approximately .45g and the repeatable high ground acceleration would be ap- proximately.29g. 33~lR_DOC 1(in9o&Jl(toon 5 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Liverpool Drive March 31, 1997 Project No. 103354-01 7.1. Ground Surface Rupture Ground surface rupture is considered more likely where known active or potentially active fault traces are located, than in other areas. Based on our evaluation, there are no known ac- tive or potentially active faults beneath the subject site. Accordingly, the potential for ground surface rupture at the site is considered low. Lurching or cracking of the ground caused by seismic events on nearby active or potentially active faults is not considered a significant haz- ard, but is a possibility. 7.2. Liquefaction and Seismically Induced Settlement Liquefaction is a phenomenon in which saturated soil loses shear strength during an earth- quake. Groundshaking of sufficient duration results in the loss of grain-to-grain contact due to rapid increases in pore water pressure, causing the soil to behave as a fluid for a short pe- riod of time. To be potentially liquefiable, a soil is typically cohesionless with a grain-size distribution consisting generally of sand and silt. Due to the relatively dense nature of the ter- race deposits, in our opinion, the potential for liquefaction of the on-site soils is negligible. Seismically induced dynamic settlement of soil is a possible result of liquefaction. Due to the negligible potential for liquefaction at the site, dynamic settlement was not evaluated and is not considered to be a concern relative to planned improvements. 8. CONCLUSIONS The proposed single-family residence, as described herein, appears to be feasible from a geotech- nical perspective. There are no known geotechnical constraints that would preclude the proposed project, provided the recommendations of this report and appropriate construction practices are followed. A summary of the findings and conclusions of our geotechnical evaluation for the proj- ect is provided below: · Geologic hazards such as deep-seated landslides or active faults are not present on the site. The site, like the rest of San Diego County, could be subjected to relatively strong ground shaking due to earthquakes on active faults in the region. 3354-0IR_DOC IY1n9D&)V\oon 6 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Liverpool Drive March 31, 1997 Project No. 103354-01 . Based on our subsurface exploration and review of the preliminary plans for the project, fill soils and terrace deposits will be the primary earth units that will be encountered during site grading. . Some portions of the terrace deposits are moderately cemented. Accordingly, some ripping may be needed to achieve proposed excavations. . Perched groundwater was encountered at a depth of approximately 3.0 feet bgs in test pit TP-2. . Based on the results of our limited corrosivity testing, the on-site soils may generally be con- sidered very corrosive to metals and have sulfate contents that are considered to be negligible. 9. RECOMMENDATIONS Based on our understanding of the project, we are presenting the following recommendations for use during the design and construction of the new single-family residence. 9.1. Earthwork Earthwork operations, including remedial removals, placement of compacted fill, and footing excavations, should be observed and tested by the geotechnical consultant. The earthwork should be conducted in accordance with recommendations presented in Appendix C, except where superseded by the recommendations presented in this report. 9.1.1. Excavations Those areas to be graded should be cleared prior to construction and should include the removal of existing structures, pavement, rubble, debris, vegetation, and any loose, wet, or otherwise unstable soils. Surficial soils in areas to be graded should be removed to competent formational materi- als prior to placing fill or backfill. The exposed surface should be observed by the geotechnical consultant to evaluate the suitability of the subgrade for supporting fill and structural loads. The exposed surface should be scarified to a depth of 8 inches, brought to near optimum moisture content, and compacted to 90 percent relative compaction as 33S4-0IR.DOC 1(ln9o&l(t.oon 7 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Liverpool Drive March 31,1997 Project No. 103354-01 evaluated by ASTM 01557-91. Surfaces on which fill is to be placed and that are steeper than 5: 1 (horizontal to vertical), should be benched as shown in Figure A of the Typical Earthwork Guidelines (Appendix C). 9.1.2. Fill Placement and Compaction All fill and backfill should be compacted in uniform horizontal lifts to a minimum relative compaction of90 percent as evaluated by ASTM 01557-91. Fill soils should be placed at a moisture content near optimum moisture. The optimum lift thickness of fill depends on the type of compaction equipment utilized, but generally should not exceed 8 inches in loose thickness. Fill material should be free of trash, debris, roots, vegetation or deleterious materials. In general, fill should generally be free of rocks or hard lumps of material in excess of 6 inches in diameter. 9.1.3. Import Fill Material Import fill material should not be required for the proposed new construction; however, if required, it should consist of noncorrosive granular material with very low expansion potential as evaluated by UBC Standard 29-2 (Expansion Index Test). The geotechnical consultant should be contacted to evaluate materials prior to importation. 9.2. Foundations The following foundation design parameters are provided based on our preliminary analysis. The foundation design parameters are not intended to control differential movement of soils. Minor cracking (considered tolerable) of foundations may occur. 9.2.1. Bearing Capacity Spread and/or continuous foundations founded in formational material may be designed using an allowable bearing capacity of 4,000 pounds per square foot (pst). This allow- able bearing capacity may be increased by one-third when considering loads of a short 3354-0IR,OOC l(in90&JV\OOt"8 8 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Liverpool Drive March 31,1997 Project No. 103354-01 duration such as wind or seismic forces. Isolated spread foundations should be tounded 24 or more inches below the existing ground surface, and should have a width of 18 or more inches. The following table presents recommended dimensions for continuous foundations. TABLE 2 - CONTINUOUS FOUNDATION DIMENSIONS Number of Floors Width of Footing Depth Below Undisturbed Supported by Foundation (inches) Ground Surface (inches) 1 12 12 2 15 18 3 18 24 The outside bottom edge of foundations should not be located closer than 8 feet horizon- tally from the face of descending slopes. We recommend that foundations be reinforced in accordance with the recommendations of the project structural engineer. :From a geotechnical standpoint, we recommend that continuous footings be reinforced with two No.4 reinforcing bars, one placed near the top of the footing and one near the bottom. 9.2.2. Lateral Earth Pressures Foundations bearing in compacted granular fill materials may be designed using a coeffi- cient of friction of 0.40 (total frictional resistance equals coefficient of friction times the dead load). Foundations may be designed using an allowable passive resistance value of 300 pounds per square foot per foot of depth, with a maximum value of 3,000 pounds per square foot. The allowable lateral resistance can be taken as the sum of the frictional resistance and passive resistance, 1 provided the passive resistance does not exceed two- thirds of the total allowable resistance. The passive resistance may be increased by one- third when considering loads of short duration such as wind or seismic forces. 9.2.3. Floor Slabs Floor slabs should be designed for their specific loads and usage. We recommend that a structural engineer experienced with such structures be consulted. The slab thickness 3354-0IR.DOC /(in9o&/(toore 9 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Liverpool Drive March 31, 1997 Project No. 103354-01 should be as recommended by the structural engineer. To help control shrinkage crack- ing, we recommend that slabs-on-grade be 4 or more inches in thickness and be reinforced with No.4 reinforcing bars placed at the midpoint of the slab and spaced at 18 inches on-center both ways. The reinforcing bars should be placed on chairs. Floor slabs should be constructed and reinforced in accordance with the recommendations of the structural engineer. Floor slabs should be underlain by a moisture barrier consisting of a 2-inch thick layer of clean sand underlain by a polyethylene moisture barrier, 6-mil or thicker, which is, in turn, underlain by a 4-inch thick layer of 3/8-inch pea gravel or equivalent. Soils underly- ing the slabs should be moisture conditioned and compacted in accordance with the recommendations contained in this report. Further, the soils should be moistened just prior to the placement of concrete. Joints should be constructed at intervals designed by the structural engineer to help reduce random cracking of the slab. Floor slabs subject to heavy wheel loads, if any, should be evaluated on a case-by-case basis by the project structural engineer. 9.2.4. Settlement We anticipate that differential settlement of structures constructed in accordance with these recommendations should generally not exceed 1/2 inch. 9.3. Retaining Walls Foundations for new retaining walls founded 18 inches or more into native terrace deposits may be designed assuming the allowable soil bearing capacity presented in Section 9.2.1. A triangular lateral earth pressure distribution may be used for design of retaining walls. It is recommended that unrestrained retaining walls be designed to resist the active pressure de- veloped by an equivalent fluid weight of 35 pounds per cubic foot (pcf) plus applicable surcharge pressures. For restrained walls, we recommend that the walls be designed to resist the at-rest pressure developed by an equivalent fluid weight of 55 pcf plus applicable sur- charge pressures. 3354-0IR.DOC 1(inao&JIft,oon 10 I I I I I I I I I I I I I I I I I I I II Mr. Stephan A. Beck 405 Liverpool Drive March 31,1997 Project No. 103354-01 The values presented herein assume level backfill, very low expansive backfill material behind the walls and free-draining conditions. Measures should be taken so that moisture does not build up behind retaining walls. Drainage measures should include free-draining backfill ma- terials and either perforated drains or collection piping with sumps. A typical retaining wall drain is shown on Figure 4. Drains should outlet away from structures. Walls should further be waterproofed in accordance with recommendations of the project architect or engineer. 9.4. Flatwork We recommend that flatwork be installed with crack-control joints at appropriate spacing as designed by the structural engineer. Exterior slabs should be underlain by 4 inches of 3/8-inch pea gravel or clean sand. Subgrades should be prepared in accordance with the earthwork recommendations presented herein. Positive drainage should be established and maintained adjacent to flatwork. 9.5. Moisture Conditioning and Concrete Placement Prior to placement of the slab underlayment and the new slab, we recommend that the sub- grade soils be moisture conditioned under the observation of the geotechnical consultant. In order to reduce the potential for shrinkage cracks in the concrete during curing, we recom- mend that the concrete be placed with a maximum slump of 4-inches based on ASTM C143. The slump should be periodically checked at the site prior to placement. We further recom- mend that crack control joints be provided in the slabs in accordance with the recommendations of a structural engineer to reduce the potential for distress due to minor soil movement and concrete shrinkage. 9.6. Soil Corrosivity The corrosivity of the on-site near surface soils was analyzed to evaluate its effect on con- crete structures, including foundations. The corrosion potential was evaluated using the results oflaboratory testing on a sample of the existing surficial soil obtained during our sub- surface evaluation. 33S4-01R,DQC l(in9o&J'ft.oon 11 I I I I I I I I I I I I I I I I I I I illl Mr. Stephan A. Beck 405 Liverpool Drive March 31, 1997 Project No. 103354-01 Laboratory testing was performed to evaluate pH, minimum electrical resistivity, and cWoride content. Sulfate content is addressed in the Concrete Placement section of this report. The pH and minimum electrical resistivity tests were performed in accordance with California Test Method 643, and the cWoride test was performed in accordance with California Test Method 422. Test results indicate that the pH of the sample of soil tested was 6.8, which is considered essentially neutral. The sample also had a measured minimum electrical resistivity of 3,600 ohm-cm, which is considered to represent a potential for heavy corrosion. The chloride con- tent of the soil sample tested was found to be 60 mg/kg, which is considered corrosive to ferrous metals. Based on these test results, the on-site soils may be considered very corrosive to ferrous metals. A corrosion specialist should be consulted for further recommendations re- garding corrosion protection for buried metallic elements that may be included in the proposed construction. 9.7. Concrete Placement In order to reduce the potential for shrinkage cracks in the concrete during curing, we rec- ommend that the concrete for pavement or other flatwork be placed with a maximum slump of 4 inches. The slump should be checked at the site by a representative of a qualified mate- rials testing laboratory prior to placement. All structural concrete should be placed in accordance with ACI and project specifications. Concrete in contact with soil or water that contains high concentrations of soluble sulfates can be subject to chemical deterioration. The soil sample tested for this evaluation indicated a sulfate content of 7 parts per million (ppm), which is considered to represent a negligible cor- rosion exposure to concrete. We recommend the use of Type II modified cement. Where reinforced concrete (i.e., foundations) will be in contact with the soil, we recommend that the concrete cover over reinforcing steel be 3 inches or more. 3354-01R.IXX: 1(ln9o&jlftoon 12 I I I I I I I I I I I I I I I I I I I 1'1"1' Mr. Stephan A. Beck 405 Liverpool Drive March 31, 1997 Project No. 103354-01 9.8. Site Drainage We recommend that surface drainage be provided to direct water away from the residence and off of pavement surfaces. Surface water should not be permitted to drain toward the residence or to pond adjacent to foundations or on pavement areas. Positive drainage is de- fined as a slope of at least 2 percent for a distance of 5 feet or more away from the structures. Roof gutters should be installed on structures. Downspouts should discharge to controlled drainage systems. Irrigation in the vicinity of the structure should be kept to a minimum. 9.9. Construction and Observation Testing The conclusions and recommendations presented in this report are based on analysis of ob- served conditions in two widely spaced exploratory test pits. If conditions are found to vary from those described in this report, the geotechnical consultant should be notified and addi- tional recommendations will be provided upon request. Project plans should also be reviewed by the geotechnical consultant prior to the start of construction. The geotechnical consultant should perform appropriate observation and testing services during construction operations, including evaluation of subgrade conditions in areas where flat work or settlement-sensitive exterior improvements, are to be constructed. The geotech- nical consultant should also observe and test the placement and compaction of fill soils. The recommendations provided in this report are based on the assumption that Ninyo & Moore will provide geotechnical observation and testing services during construction. In the event that it is decided not to utilize the services of Ninyo & Moore during construction, we request that the selected consultant provide the client with a letter (with a copy to Ninyo & Moore) indicating that they fully understand Ninyo & Moore's recommendations, and that they are in full agreement with the design parameters and recommendations contained in this report. Construction of proposed improvements should be performed by qualified subcontrac- tors utilizing appropriate techniques and construction materials. 33~IR.DOC 1(iIlflO&JV\oon 13 I I I I I I I I I I I I I I I I I I I "I Mr. Stephan A. Beck 405 Liverpool Drive March 31, 1997 Project No. 103354-01 10. LIMITATIONS The field evaluation, laboratory testing, and geotechnical analyses presented in this geotechnical report have been conducted in general accordance with current practice and the standard of care exercised by geotechnical consultants performing similar tasks in the project area. No other war- ranty, expressed or implied, is made regarding the conclusions, recommendations, and opinions presented in this report. There is no evaluation detailed enough to reveal every subsurface condi- tion. Variations may exist and conditions not observed or described in this report may be encountered during construction. Uncertainties relative to subsurface conditions can be reduced through additional subsurface exploration. Additional subsurface evaluation will be performed upon request. Please also note that our evaluation was limited to assessment of the geotechnical aspects of the project, and did not include evaluation of structural issues, environmental concerns or the presence of hazardous materials. This document is intended to be used only in its entirety. No portion of the document, by itself, is designed to completely represent any aspect of the project described herein. Ninyo & Moore should be contacted if the reader requires additional information or has questions regarding the content, interpretations presented, or completeness of this document. Our conclusions, recommendations and opinions are based on an analysis of the observed site conditions. If geotechnical conditions different from those described in this report are encoun- tered, our office should be notified and additional recommendations, if warranted, will be provided upon request. It should be understood that the conditions of a site can change with time as a result of natural processes or the activities of man at the subject site or nearby sites. In addi- tion, changes to the applicable laws, regulations, codes, and standards of practice may occur due to government action or the broadening of knowledge. The findings of this report may, therefore, be invalidated over time, in part or in whole, by changes over which Ninyo & Moore has no con- trol. This report is intended exclusively for use by the client. Any use or reuse of the findings, conclu- sions and/or recommendations of this report by parties other than the client is undertaken at said parties' sole risk. 3354-01R.DOC 1(ln9o&1ft,oon 14 I I I I I I I I I I I I I I I I I I I 111'1,',1'1 Mr. Stephan A. Beck 405 Liverpool Drive March 31,1997 Project No. 103354-01 11. SELECTED REFERENCES Anderson, J.G., Rockwell, T.K., and Agnew, D.C., 1989, Past and Possible Future Earthquakes of Significance to the San Diego Region: Earthquake Spectra, Volume 5, No.2, EERI. Department of the Interior, United States Geological Survey, 1968, Topographic Map, Encinitas Quadranqle, 7.5 Minute, photorevised 1975. Eisenberg, L.I., 1985, Pleistocene Faults and Marine Terraces, Northern San Diego county in Ab- bott, P.C.(ed) On the Manner of Deposition of Eocene Strata in Northern San Diego County: San Diego Association of Geologists. Jennings, C.w., 1994, Fault Activity Map of California and Adjacent Areas: California Division of Mines and Geology, California Geologic Data Map Series, Map No.6, Scale 1 :750,000. Mualchin, L., and Jones, A.L., 1992, Peak Acceleration From Maximum Credible Earthquakes in California (Rock and Stiff-Soil Sites): California Division of Mines and Geology, DMG Open-File Report 92-1. Norris, R.M., and Webb, R.w., 1990, Geology of California, Second Edition: John Wiley & Sons, Inc. Ploessel, M.R., and Slosson, J.E., 1974, Repeatable High Ground Accelerations from Earth- quakes; Important Design Criteria: California Geology, September, p. 195-199. Seed, H.B., and Idriss, I.M., 1982, Ground Motions and Soil Liquefaction During Earthquakes, Volume 5 of Engineering Monographs on Earthquake Criteria, Structural Design, and Strong Motion Records: Berkeley, Earthquake Engineering Research Institute. State of California, 1992, California Code of Regulations, Title 8 Construction Safety Orders, Appendices A and B: Register 92, No. 43, dated October 23. Uniform Building Code, 1994: International Conference of Building Officials, Whittier, Califor- rua. Wesnousky, S.G., 1986, Earthquakes, Faults, and Seismic Hazards in California: Journal of Geo- physical Research, Vol. 91, No. B12. AERIAL PHOTOGRAPHS Source Date Flight Scale Numbers USDA 78 and 79 1:20,000 05-02-53 AXN-8M 33S4-0IR.DOC /fiD90&1f.oore 15 I I I I I I I I I I I I I I I I I I I '1111 11; ~"c OJ~;' "'~'\t~: @: ;.~1-':'.~; ~ g :15 DI~;;:;I~f,i~~;: ;';)~~i~h ~~4~-~'~';~\~~1~~IJ' l';';;":'~"\~~.;';~ \'i~' ~ _~ l:: ~ 8 iii 3 ~ HS. :r:-HNi15~..J .,"';:).... ~ A~H(ljO c.I;~: 1~li113 \\ u PO .~:: ~ ~ Ol(;! g ~ ~ ~ ~~ 100 l1li ~ 900 ~"" ~ Pl l><l Ii Ht:1Jl oRl~ ~ fVri DE ,S MiEL5~ lAE("~ ,~ -- <=> ~... VI Q. - FE >- W4lN eC~(H'" . ~AAllGrm. Ii LH "- K S U 600 . SANTA gll 1100 8 ::j 0: r ~ DR ~ "'. 'O-W- ,'>."'f i'i I\,. \..,\ :~:"'>I.It4J1M1~T1;'H~SC~~I~~~FA!RHAV::;~~' !i!~l .. ~ ;:!O--'.IL,;OOl ~Tt\'" -\.\\", X -T.'\r \-- .J;J l~;~ ~-'1*~ ~NCIIf1T/.S ~~..! 7;' ?lKlNEVAR '3 ~ t"~ O~ ~ ~ VYGl[H ~~'f>:\~:i:l'lt':i\"~~llir S!"~' 1,,11_ ~~'" O'~ --;~I 't,. ~ CA1H1IUllNl~ ~ ... ""I~~~ c--, OR '"'Ii! tl \ K'\ ,..",,,'\ ~ 10: '" ~ ""0: 1": 0:: P/iffOOOO DR __ . I IFF S' YJI~ ~ \ 1~~1.P /JImsTR[lI~.~~~~.o \t> C TnD.R,g=__ ~ 1400 JJ.!!H~(~~~~p!. ___~__~ ~~'" ~ ~2'-n::_1 ~ ;::~~ROS\OIl;fl 9O(lCr -p lOR DR ~1ClH.lR[aW i\- <~:-: CARDIFF- ~,~" ~I \~1uJ~"'" """;~"''' ~;\\"~ ,-- .. ~~w~, ~ l)[ iil ~f~ C UK CT c""I '\:" dS! R1A~ BY - THE -SEA "'~ a: ~ ~\~" .,:' ,000""' 6 ~ ra l~' , \~1? ~ "~A~ ~ SA1IOO.Sm~R ':In!; CAROIFF _ l[NNIS cLege::: ~ ~~l...IUAV NO~900l!l~/:i DR;::::- DR ". {t, ,.... ~"""".;"'" ~ \\.%,*,",'~(;\.'"' " ~:.ftJi A" ~ ,Af ~~~~Li Ii! JUDY m \t,.:;:;.J: ~ ~';5 e.,.:J"; ~ ~~" ~ ~ 2:. - ~ ~ _ atRM.l _ ,. WJfJ, ~ ~. "00 OR / STATe ,. \'"~\" ~ ~\\ ~ ;13 I~ 8 ~ ~ """ '. :, ~'" ~ . - ~~g ENe IoNI1! ~ \. {~.. "~" ~"- Sl!.~ 1'1< ~~ ~ .. ~)\ I~;~'~~\'I~ ',,' c' -, l ~." ~ '~~~o.~,i 1!~' , \~ ." ~(;'\\;" ,0 ~ "Iii ."",." ,\)~ P ~%" '!J:.';;!i: f, 1"1;10 .,..... 0 JOO:1 Oil. "-v S~ - Q;LlfGE r .;;c \'\) ~..~ .~~'- ~ fl)" ~' ~1'~'J.X '". ~ '" ......~I( <e:';' , 7" 0,. .. /;; M' ~' ~,,,, ...;~ '0", i'" ~ " ,'to ~~ l::'. '- v ~NCHFS,[[l:, " \~':7"\~ '1.. 26,.*''''''- \......?'\'f ~ ~tY ~ h '~~t.~ /~c1De~:;(;',.: ~ \ \ "~;;: /:d~~'tl\ :~~ij l , . ."JSi~\t~j~ Ie ,Y'"""," e,., ~\I\..~,'l i'C\" I--\..o~~" 1~: .,:~,~~:> ~ ::;;, ;:'~. ~~''ir~ , )\~ ( ;I~ ~'~~'v~~ ,../; Nb.p ': __ ~\-~I-:\.., ,,~I,I, j~j ',', ';;\, ,.\p-. ' ~&: 13 ~ ~., HELENA l' SUN\.'/ "oJ' 2' ""-~:;;; -<~r.jp" ,.... .,~ ;p><jf;'f. 600 ~~~ ~t :i, '$ PATTY Hll ~ '0.",;::;;t'P.;c: ~.r~~\ ~ .. J~~t~. ~. .~ '00 "' 'O"oU ;;: ">,,...~ ~g~ ,..-- -'''';''-:''"'''00, 1'~~~Jl,.' ;('11\ '.~/!,,f,2 c"~'^~f~"H,t'il~~~6'1lo.f~1 p~ ~ '3,;'ie ~ I 'ft'~'~ 5000 L s...j '?~ 0. ~/(~'O,'~ OR ~ Ie ',<-\1",\ \~ . \ IS. 0 e ,;d!51~ ", . --- - '" ~"'" \l ,'(; [\C1F' <;J./tSf'"" t,-ti ...( ~'" " ;!it:Vl,\ '\~~ i\'\ \' ~~" \'~~;.;; !;.~1i;~~"- E '~.::1! PAR: ~i~~': r' \$~. ,.<>".. "" """ 11. JJ <<Z)"-,? ~ ,~, "" JRHS OOOL'O ~ _'" lilt .Z8~:IQ.:.;~. ,~.:.: ?<< z V> '!Ill. ~ ''''''N~311(:lt~\5''''-'''' 'i..~l "Uil ~i;- !J~~~6~~___ ",M_--~~J~tSLA-""':.~./'- ~~ cc~ '" ~ T145 :i.. "" ~,.~. ~1E~IM' fLETCH[R~;;:.S ~p:r"\~~j;, ~ ~ Cn"t;.fU~",~ nO ~ ~ ~ ,~,cr7' J.-- o ;;@ , 5'" ~1 '~.NO cir;L~ 24 ..,CIl!ST '" t ~ ."t> -.""- ~1'" ," I,,;$g.;:- ~~\-'?'\ ~, ~ ~ ......... ~ ......... o , ~... ~ i!;'0-.' I 1:/':.;[::'; '(. ,~ c.7 ,_ L-d,;'c. ~G~ L_~i~5~i 5 ..... C> '" ~ Z SEE\f!H7 'ILLA"I_IT lOtW;WllllOCT 1""'IWorr Z\ lI....Of\U .=~ 1("".I;AU 1JJ'Wlrr I_ICOO l' ]Gll\LACT SIll'l{ll.tT z<;lAS....II/oSCl IAlTlllOCT 16010ll'ltW W.l"C~ln 1/ 'LU'D! CT WI"'ICT 16llU(>IliE.1\JIllCl ~lJW,oc.\Cl 19tn""'Cl .t'lrY.>In lDt>W"LACT \A810A1>1l 11COli.><El1T ,1)0105U 31 DCU(I'Ser ..,,'" lllAA'<JCT """lIlJIIOStT :w IlISOI'.lOO Wr..o.ou.SIN 1\ (tJAUJ1"'OCT REFERENCE: 1994 Thomas Guide for San Diego County, Street Guide and Directory .... NORTH o I 2400 4800 ( Approximate Scale in Feet ;' SITE LOCATION MAP BECK RESIDENCE 405 LIVERPOOL DRIVE CARDIFF-BY-THE-SEA, CALIFORNIA ( FK31RE ) If/RHO &JV\OOI'8 '- PROJECT NO. 103354-01 DATE 3/97 ... -S'ij-. . --.ill! - \ "T , ' \ I __.+L: ::1 ;<& / . --. . .-.--.- ~T , GO i?~ ~ <.,,~ j, '- \ \ '\ -- ---_._----~-- n Ii i , 1911'-- I , i I I I --..- ")jJI - .-r------ I..!;-- ,- \1l, :;>1 -, (\Ii c.j .---- 1f( , --~ ~~I CL. !Li'~, ~i .1, ")il- 1 ~I I' ~ L-/ .5-L/-'-: , , ! .------------ P~/- --- r GoJ-- - I , I ----~--- i; I -- -~---- ...--- --~---- -~- , \ C' ~ '3 .., c_ , , I i S, \J \ S,I :::J , , , ! '" It , I L_T' ,I UI _\ '-'l .~ J" '\- C\ ""- Ul ~ ~ \S' ~ Cj lt~ --_J --~ ,-. 1 I : _JL~ "=~ " --=: L: i \I.> ---- -------- / \ .\\ \0 , '-, ~ ""\" '\' ! .3l"..,.,.? H__....~~_ ''"\ ~'.'Ilc..:'_-:...~___ \ 0 "<'./. 0 \ nD-,~6" _....---'--/ ------ /--- ILI- - - all -.-" -.. , ? / '...............~~---. ~,.. ----- " ... , \ '. '. ..:.' " ,J.-:_.... \ .lJ.:.>!,CXJ,ol 01,;: N <Y/ .:.'\ I- I ! I, Iii Iii n- - ,- li-- 1,-- - 5- Ii I I , 1 I , , I G " 1 I ~ i I I,u I I . " !I-~ Ii II 0 <SJ I '" z I I __J ,I I I: '-I [ -=-=--~-__~ -~,-c;-~~~ ~~'-,:!~-"-.-....,, / ---f~ '\ \ ... ,00 G>; '''-,.M "q?,ol "I~ N .... '. ----,r-- \~ \-,-. \ \ II . \ . I." II ~~ll \ ~'\ ~ \, II "_ \\\\.\ ",)~__ _ r<t-----\,-=-- ____ .__. ..........de-\ r ;;r-~~------ \. ", '-I i ~ r- i I \ '\ If e: \\ \~ lJ r- -=--- ~ ~------- irt , is '~ ~ \ -----.------ \, \ ~~- " <-;: ~ \ '~"\\ & \, :.--- \ \ \ \ ~ /\ \ \:; \ ,<;"...... \ C> "" , , , '\ ~ "- ..., " , '\ '\ '\ .~ ". " c' <;;.- , , " :3 [l N :3 A -V -;j 0ClI GI 9 v-I-v':::) ~......-> ~ ---- -~- 1'1 I a. <( :$ ::!: z z c: o 0 ~ w~ <.) w>...J <.)0:<( g ZClc.: I- W...J<( - Clow a. oooCl) I- wa.' CI) c:c:w w ::.::w~ I- <.)>1 Cl w...J>- Z a:lLOa:l <( 01 Z v!t <( u: ...J c: a. <( w <.) I- 00 CI' 15 ~ o\j ~ .S ~ ... 0> 0> ~ ,.: ~ l.l :a ::;: '0 " OJ > " ~ " " .2 OJ l.l .2 - a. ;; $ $ " E .~ Q Cl Cl Z <( W Cl W ...J I C'oI I A. ~ w c: ::lC\l Cl u: w " ~ ~ Cl M o Z ~ I- ? <.) v UJ LO .., M o M c: 0 a. ~ o '" - CIl CIl - o ~ o LO o ~ .!! '" () '" I I I I I I I I I I I I I I I I I I I '11: III 4..... \~ \ l\ \ . BAKER SAN IlUAlIlND CD. AMBOY . '\. DESERT CENTER . "'.. '1-;. .. ~ KIVlUIDl CD. ------;;,;liiAiu-- .~....."''' SAN CLEMENTe.. ... '.' '. ~. ".. ISLAND': . _ <~_ \~.", <" o I scale 30 60 I miles " "-- FAULT LOCATION MAP BECK RESIDENCE 405 LIVERPOOL DRIVE CARDlFF-BY- THE-SEA, CALIFORNIA IfJn90&~oot'e I PROJECT NO. DATE ..., I \. 103354-01 3/97 I ..... ~ C FK33RE ) \.. I I I I I I I I I I I I I I I I I I I III ~l CLASS 2 PERMEABLE MATERIAL SIEVE SIZE 1" 3/4" 3/8" No.4 No.8 No.3D No.50 No.200 PERCENT PASSING 100 90-100 40- 1 00 25- 40 18-33 5-15 0-7 0-3 INNER WALL SURFACE TO BE WATERPROOFED IN ACCORDANCE WITH THE SPECIFICATIONS OF THE PROJECT CIVIL ENGINNER RETAINING WALL FINISHED GRADE 1 ~Y~Y~Y'-' /". /);y);. /' COMPACTED WALL FOOTING . BASED ON ASTM D1557-91 l' VARIES SOIL BACKFILL, COMPACTED TO AT LEAST 90 PERCENT RELATIVE COMPACTION . 3/4" TO 1-1/2" CLEAN GRAVEL" APPROVED FILTER FABRIC ENVELOPE 4" DIAMETER PERFORATED SCHEDULE 40 PVC PIPE OR EOUIVALENT INSTALLED WITH PERFORATIONS DOWN. MINIMUM 1 PERCENT GRADIENT TO JUST BEYOND WALL AND THEN NON- PERFORATED PIPE TO STREET OR SUITABLE OUTLET. ** IF CALTRANS CLASS 2 PERMEABLE MATERIAL ( SEE GRADATION ABOVE) IS USED IN PLACE OF 3/4" TO 1-1/2" GRAVEL, FILTER FABRIC MAY BE DELETED. CALTRANS CLASS 2 PERMEABLE MATERIAL SHOULD BE COMPACTED TO 90 PERCENT RELATIVE COMPACTION NOT TO SCALE c:\d..~s\ne..\woI12,d"'9 ~ MintlO&AADDre~r TYPICAL ~ -. ,- 'ii' · , · '-.RET AINING WALL DRAIN DETAIL) ~ I I I I I I I I I I I I I I I I I I I I' 'I" ... Mr. Stephan A. Beck 405 Liverpool Drive March 31, 1997 Project No. 103354-01 APPENDIX A FIELD SAMPLING PROCEDURES Disturbed Samples Disturbed soil samples were obtained in the field using the methods described in the subsequent section. Bulk Samples Bulk samples of representative earth materials were obtained from the exploratory excava- tions. The samples were bagged and transported to the laboratory for testing. Relativelv Undisturbed Samples Undisturbed soil samples were obtained in the field using the methods described in the subsequent section. The Split-Barrel Knocker Bar Sampler The sampler, with an external diameter of 3.0 inches, is lined with I-inch long, thin, brass rings with inside diameters of approximately 2.4 inches. The sampler is manually driven into the ground with an approximately 20-pound hammer. The samples are removed from the sample barrel in the brass rings, sealed, and transported to the laboratory for testing. 33S4-01R.DOC I '!"I! I I I I I I I I I I I I I I I I I I I , c.. E- o Z f- >- c:: c:l f- 0 w en el w f- el Z 0 0 -' i= l1. a: U z en 0 w i= c oJ z <l: ~ 0 > 0 <l: w i= u ~ i:' oJ f- <l: X ~ " ~ <l: > > w 'a ~ > w oJ <l: -' u. " oJ ... w 0 Z j '0 ... " u 1l j " ;; x 0 0 0 Q. ~ oJ w z 0 i= ~ 8 ~ '0 eo w ::> :I: <l: " ~ g " f- 0 f- > '0 ... ~ . tl' u ,~ l;j :; e <l: 0:: w 0 ... 0 0 el :2 -' 0 '" c:l Z el '" 's':)'s'n NOI.l 'If:)I~ISS'lfl:) (~:)d) A.lISN30 Al:lO I (%) 3l:ln.lSIOIN ~II' 0. auo:) pues ~ I S31dlN'lfS UaAPO I_ I ~ln8 I (.l33~) H.ld30 0 - '" M ... '" '" I !Io.. CU w "Y-> ~~ f- a.. <l: " 0 ~ eo I~ c:J j I 0 ;;; I~ ...J t; I- " i:- E- . i' a:: .... ~ 0 ~ " ~ I- .9 J CJ) ;; w l;j I- ~ 0 ~ ..: It - w z - f- " "-""" -., u " w ..., - 0 II 0:: I "- w -' <l: u en FIGURE I ~ >, "" ..d - "" ~ ~ I >- ]' CD a 0 " z w ~ f- <.? " c: <.? u I a >, f- ...J 1 rJl w f- Z - I 0 ~ -H 1 i= .~ "l c.. o . " - 12 -~ ~ 00 ::. ,,-Z - - u eo ]' - z " II) "". ~~ '" u ~ '" . a Ii w Oi .; " '"jl f= c 'C 1l '0 ~ "'. :s ..~~ II ~ <( ~ " u .; Z " ~ .S ..d~ a > P:: rn.rn "" u 0 <( N f-.o >, Ii - ,&8,..: f= .... I~ "il w u 0 .8 _0_ " ~ 0"'" f- <( rn-- ~ ,,- X - 0<1)';;] 2 ~ N <( > w ~ u :; -'=' ~ ]2(;:; '" ~ "- 00 >, j > w ~ "" U-l;o;::l Oi <( ...J U. ~ " 8 ~eu= a O...d .3 > ~ 0 u w Z ~ 000 - I x 0 0 a 0:: 1.LI..r::;': P:: '" ~-g "jl -i u.~ (I).. '7 w z a f= ~ 'K - &16= w ::l :r: <( > 0 -<~~ '" - '" -.<<= f- a f- u -< ~ P::o>' - N '" !!I ~~ <( cc w a P:: P::.", @ @ @ 00", ::E :S ~CD- f-<Z"" I 0 <.? ...J 0 f-< U 'S'J's'n NOLL \fJI~ISS\flJ I .,., ~ (~Jd) A.lISN30 ABO ~ - - - . . I ~ '" '" '" (%) 3Bn.LSIOL<\l 0 ~ - - '" " ~ ~ '" auoJ pues ........ I S31dL<\l\fS ua^!JO ~ln8 (.l33~) H.ld30 0 ~ '" '" '" '" '" I I . I " '\ U 8 N W " .... '" f- Is '" '" <( - '" e 0 ~ I t C-' ~ 0 Oi "u ...J U _ I E:t: I- "".~ 'VJ "E c:: " '" ~ p::u ~ I- -"'oJ' ~ (J) il.~ I w ""0 / I- "8 a ...: t z - .... e- 9 - " f- '" - I > u '" ,!: j w '" / ...., '" - '" a 8 0 II '" cc I "- w I ...J <( U rJl Ill' I FIGURE 1 1111' IN ~ ~ ~ >. ell 1 >- Cl Ig m ';< >. [ ';l 0 ~ w l- t:) -8 ~ "ill a:: t:) 'in Q 1 ] 0 '€ ] I- -' ~ VI 0 w Z '" ~ I ~ I- ~ Z '" S >. 'C 0 'in >. "il . 1 0 i= 1 - 1 +i ~ 1 "il '" II.. ~ ';< r- 12 ] 0> r- ::0 ~ e - - ~ u 1i - B El 0. - Z l/) '~ . j _' 0. '" il " " 0" 0 w 1 " .- f= "" Q o~ o '" .. '~ _z ,,; " IIll z <( 0.0 "" il oS E . 0 > e<: ~ <i;ElI- ,9 - ~~ f= <( ... I-~<Il ] B il'''r- u 0 ~ - 0 ~ 0"0> <( X - '" -~ 8;::;; ~ 0" > w " r ... llil<;; w ~ fii ~<Il 0 II <( -' u. ~ '@ ~""'C1 W 0 z 1/5 oS >.B 0 ~~ 0 0 0 .J:J u.l,J:::l..... m ~ ....ll El I~l; ~~- z 0 f= ~ ~]G3 :J I <( ""~ - N 0 I- u ~I~j ~~~ N '" So-tj <( a:: w 0 @ @ 0-'" 0 t:) :2 -' ...Om f 's'J's'n ::E NOli\fJI~ISSVlJ '" l (~Jd) AilSN30 Al:lO on :! - . . N N r- (%) 3l:lniSIOVII - - ~ I', ~ '" N - - - - auoJ pues .... S31dVII\fS U9h!JO f 'ling U33~) Hid30 0 - N .., .. on '00 II r- Ie 8 w N r- 0> I- 0> .. <( - 0 '" !t e ~ ~ 0 .. "U ....I u _ ill!:: I- ""'~ ,."" ~ 0: ~a ~ I- "" - ~ ~ VJ 'c w "'0 l- I 0 .; l z - - I- 9 - " .. - > u on ,5 ;:l w .., ) -, .., I - on 0 0 0 - I .. a:: II a.. w DNII00J -' <( I I u CfJ I FIGURE A-2 I I I I I I I I I I I I I I I I I I I f Mr. Stephan A. Beck 405 Liverpool Drive March 31,1997 Project No. 103354-01 APPENDIX B LABORATORY TESTING Classification Soils were visually and texturally classified in accordance with the Unified Soil Classification System. Soil classifications are indicated on the logs of the exploratory excavations in Appen- dixA. In-Place Moisture and Density Tests The moisture content and dry density of relatively undisturbed samples obtained from the explora- tory excavations were evaluated in general accordance with ASTM D 2937-94. The test results are presented on the logs of the exploratory excavations (Appendix A). Direct Shear Tests Direct shear tests were performed on undisturbed and remolded samples in general accordance with ASTM D 3080-90 to evaluate the shear strength characteristics of selected materials. The samples were inundated during shearing to represent adverse field conditions. The test strain rate was 0.005 inch per minute. Results are shown on Figures B-1 through B-2. Maximum Dry Density and Optimum Moisture Content Tests The maximum dry density and optimum moisture content of selected representative soil samples were evaluated in general accordance with ASTM D 1557-91. The results of these tests are sum- marized on Figure B-3. Soil Corrosivitv Tests Soil pH, water pH, and resistivity tests were performed on representative soil samples in general accordance with Caltrans Test (CT) 643. The chloride content of selected samples was evaluated in general accordance with CT 422. The sulfate content of selected samples was evaluated in gen- eral accordance with CT 417. The test results are presented on Figure B-4. 33S4-0IR,OOC I Rev. 2/97 I I I I I I I I I I I I I I I I I I I ~ lij 1500 Q. ~ (/) (/) w !: (/) ~ 1000 J: (/) Description Slightly SIlty SANDSTONE G:335.(Ollll 2000 500 o o 1000 1500 500 2000 2500 NORMAL STRESS (PSF) Boring Shear Cohesion Friction Symbol Number Strength Depth (Feet) (PSF) Angle Soil Type . TP-1 PEAK 330 3.5- 4.5 250 FORMATIONAL DIRECT SHEAR TEST RESUL TS BECK RESIDENCE 405 LIVERPOOL DRIVE CARDIFF-BY- THE-SEA, CALIFORNIA (FKlliREl ~ _/(in9D&1V'aare , PROJECT NO. DATE ') \ 103354- 01 3/97 } I I I I I I I I I I I I I I I I I I I ~ lJi 1200 Q. ~ (/) (/) w g: (/) ~ 800 ill Description Remolded @90% Re. G,335401B2 1600 400 o o 400 800 1200 1600 2000 NORMAl STRESS (PSF) Boring Shear Cohesion Friction Symbol Number Strength Depth (Feet) (PSF) Angle Soli Type . TP-1 PEAK 320 3.5- 4.5 240 SM-SP DIRECT SHEAR TEST RESULTS BECK RESIDENCE 405 LIVERPOOL DRIVE CARDIFF-BY- THE-SEA, CALIFORNIA PROJECT NO. DATE ~ 103354-01 3/97 ~ _lfin90&~DDre_ SAMPLE MAXIMUM DRY DENSITY (PCF) OPTIMUM MOISTURE CONTENT (%) SOIL DESCRIPTION TP-1@3.5'-4.5' Orange brown silly SAND 125.5 10.3 G:335401B3 PERFORMED IN GENERAL ACCORDANCE WITH ASTM 01557-91 MAXIMUM DENSITY TEST RESUL TS -1(in90 &1V'oore_ BECK RESIDENCE 405 LIVERPOOL LANE CARDIFF-BY- THE-SEA, CALIFORNIA ~ ~ ~ PROJECT NO. DATE , 103354- 01 3/97 J RESISTIVITY * SULFATE CONTENT ** CHLORIDE SAMPLE LOCATION * CONTENT *** pH (ohm- em) (ppm) (ppm) TP-2@2'-3' 6,8 3,600 7 60 * California Test Method California Test Method *** California Test Method 643 417 422 ** G:33540184 CORROSIVITY TEST RESULTS BECK RESIDENCE 405 LIVERPOOL DRIVE CARDIFF-BY- THE-SEA, CALIFORNIA ~ ~ 1(inao &JV\oore_ I PROJECT NO, DATE "\ , 103354- 01 3/97 } I I I I I I I I I I I I I I I I I I I lYPlCAL EARTHWORK GUIDELINES 1.0 GENERAL 1.1 These guidelines and the standard details attached hereto are presented as general procedures for earthwork construction. They are to be utilized in conjunction with the approved grading plans. These guidelines are considered a part of the geotechnical report, but are superseded by recommendations in the geotechnical report in the case of conflict. Evaluations performed by the consultant during the course of grading may result in new recommendations which could supersede these specifications and/or the recommendations of the geotechnical report. It is the responsibility of the contractor to read and understand these guidelines as well as the geotechnical report and approved grading plans. 1.2 The contractor shall not vary from these guidelines without prior recom- mendations by the geotechnical consultant and the approval of the client or his/her authorized representative. Recommendations by the geotechn- ical consultant and/or client shall not be considered to preclude require- ments for approval by the jurisdictional agency prior to the execution of any changes. 1.3 The contractor shall perform the grading operations in accordance with these specifications, and shall be responsible for the quality of the finished product notwithstanding the fact that grading work will be observed and tested by the geotechnical consultant. 1.4 It is the responsibility of the grading contractor to notify the geotechnical consultant and the jurisdictional agencies, as required, prior to the start of work at the site and at any time that grading resumes after interrup- tion. Each step of the grading operations shall be observed and documented by the geotechnical consultant and, where necessary, reviewed by the appropriate jurisdictional agency prior to proceeding with subsequent work. 1.5 If, during the grading operations, geotechnical conditions are encoun- tered which were not anticipated or described in the geotechnical report, the geotechnical consultant shall be notified immediately and additional recommendations, if applicable, may be provided. 1.6 An as-graded report shall be prepared by the geotechnical consultant and signed by a registered engineer and certified engineering geologist. The report documents the geotechnical consultants' observations, and field and laboratory test results, and provides conclusions regarding whether or not earthwork construction was performed in accordance with the geotechnical recommendations and the grading plans. I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 liverpool Drive Typical Earthwork Guidelines Recommendations for foundation design, pavement design, sub grade treatment, etc., may also be included in the as-graded report. 1.7 For the purpose of evaluating quantities of materials excavated during grading and/or locating the limits of excavations, a licensed land surveyor or civil engineer shall be retained. 1.8 Definitions of terms utilized in the remainder of these specifications have been provided in Section 11.0. 2.0 OBLIGATIONS OF PARTIES 2.1 The client is ultimately responsible for all aspects of the project. He/she or his/her authorized representative has a responsibility to review the findings and recommendations of the geotechnical consultant. He/she shall authorize the contractor and/or other consultants to perform work and/or provide services. During grading the client or his/her authorized representative shall remain on site or remain reasonably accessible to the concerned parties to make the decisions necessary to maintain the flow of the project. 2.2 The contractor is responsible for the safety of the project and satisfactory completion of grading and other associated operations, including, but not limited to, earthwork in accordance with the project plans, specifica- tions, and jurisdictional agency requirements. During grading, the contractor or his/her authorized representative shall remain on site. The contractor shall further remain accessible at all times, including at night and during days off. 2.3 The geotechnical consultant shall provide observation and testing services and shall make evaluations to advise the client on geotechnical matters. The geotechnical consultant shall report findings and recom- mendations to the client or his/her authorized representative. 2.4 Prior to proceeding with any grading operations, the geotechnical consultant shall be notified at least two working days in advance to schedule the needed observation and testing services. 2.4.1 Prior to any significant expansion or reduction in the grading operation, the geotechnical consultant shall be provided with two working days notice to make appropriate adjustments in schedul- ing of on-site personnel. 2.4.2 Between phases of grading operations, the geotechnical consul- tant shall be provided with at least two working days notice in advance of commencement of additional grading operations. 2 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Uverpool Drive Typical Earthwork Guidelines 3.0 SITE PREPARATION 3.1 The client, prior to any site preparation or grading, shall arrange and attend a pre-grading meeting between the grading contractor, the design engineer, the geotechnical consultant, and representatives of appropriate governing authorities, as well as any other involved parties. All parties shall be given at least two working days notice. 3.2 Clearing and grubbing shall consist of the substantial removal of vegetation, brush, grass, wood, stumps, trees, tree roots greater than 112- inch in diameter, and other deleterious materials from the areas to be graded. Clearing and grubbing shall extend to the outside of the proposed excavation and fill areas. 3.3 Demolition in the areas to be graded shall include removal of building structures, foundations, reservoirs, utilities (including underground pipelines, septic tanks, leach fields, seepage pits, cisterns, etc.), and other manmade surface and subsurface improvements, and the backfilling of mining shafts, tunnels and surface depressions. Demolition of utilities shall include proper capping or rerouting of pipelines at the project perimeter, and abandonment of wells in accordance with the require- ments of the governing authorities and the recommendations of the geotechnical consultant at the time of demolition. 3.4 The debris generated during clearing, grubbing and/or demolition operations shall be removed from areas to be graded and disposed of off site at a legal dump site. Clearing, grubbing, and demolition operations shall be performed under the observation of the geotechnical consultant. 3.5 The ground surface beneath proposed fill areas shall be stripped of loose or unsuitable soil. These soils may be used as compacted fill provided they are generally free of organic or other deleterious materials and approved for use by the geotechnical engineer. The resulting surface shall be evaluated by the geotechnical consultant prior to proceeding. The cleared, natural ground surface shall be scarified to a depth of approximately 8 inches, moisture conditioned, and compacted in accordance with the specifications presented in Section 5.0 of this document. 3.6 Where fills are to be constructed on hillsides or slopes, topsoil, slope wash, colluvium, and other materials deemed unsuitable shall be removed. Where the exposed slope is steeper than 5 horizontal units to 1 vertical unit, or where recommended by the geotechnical consultant, the slope of the original ground on which the fill is to be placed shall be benched and a key as shown on Figure A of this document shall be provided by the contractor in accordance with the specifications presented in Section 7.0 of this document. The benches shall extend into 3 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Liverpool Drive Typical Earthwork Guidelines the underlying bedrock or, where bedrock is not present, into suitable compacted fill as evaluated by the geotechnical consultant. 4.0 REMOVALS AND EXCAVATIONS 4.1 Removals 4.1.1 Materials which are considered unsuitable shall be excavated under the observation of the geotechnical consultant in accor- dance with the recommendations contained herein. Unsuitable materials include, but may not be limited to, dry, loose, soft, wet, organic, compressible natural soils, fractured, weathered, soft bedrock and undocumented or otherwise deleterious fill materi- als. 4.1.2 Materials deemed by the geotechnical consultant to be unsatisfac- tory due to moisture conditions shall be excavated in accordance with the recommendations of the geotechnical consultant, watered or dried as needed, and mixed to a generally uniform moisture content in accordance with the specifications presented in Section 5.0 of this document. 4.2 Excavations 4.2.1 Temporary excavations no deeper than 5 feet in firm fill or natural materials may be made with vertical side slopes. To satisfy CAL OSHA requirements, any excavation deeper than 5 feet shall be shored or laid back at a 1:1 inclination or flatter, depending on material type, if construction workers are to enter the excavation. 5.0 COMPACfED FILL Fill shall be constructed as specified below or by other methods recommended by the geotechnical consultant. Unless otherwise specified, fill soils shall be compacted to 90 percent or greater relative compaction, as evaluated in accordance with ASTM Test Method D1557-91. 5.1 Prior to placement of compacted fill, the contractor shall request an evaluation of the exposed ground surface by the geotechnical consul- tant. Unless otherwise recommended, the exposed ground surface shall then be scarified to a depth of approximately 8 inches and watered or dried, as needed, to achieve a generally uniform moisture content at or near the optimum moisture content. The scarified materials shall then be compacted to 90 percent or more of the maximum density. The evaluation of compaction by the geotechnical consultant shall not be 4 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Uverpool Drive Typical Earthwork Guidelines considered to preclude any requirements for observation or approval by governing agencies. It is the contractor's responsibility to notify the geotechnical consultant and the appropriate governing agency when project areas are ready for observation, and to provide reasonable time for that review. 5.2 Excavated on-site materials which are in general compliance with the recommendations of the geotechnical consultant may be utilized as compacted fill provided they are generally free of organic or other deleterious materials and do not contain rock fragments greater than 6 inches in dimension. During grading, the contractor may encounter soil types other than those analyzed during the preliminary geotechnical study. The geotechnical consultant shall be consulted to evaluate the suitability of any such soils for use as compacted fill. 5.3 Where imported materials are to be used on site, the geotechnical consultant shall be notified at least three working days in advance of importation in order that it may sample and test the materials from the proposed borrow sites. No imported materials shall be delivered for use on site without prior sampling, testing and evaluation by the geotechnical consultant. 5.4 Soils imported for on-site use shall preferably have very low to low expansion potential (based on UBC 18-2 test procedures). Lots on which expansive soils may be exposed at grade shall be undercut 3 feet or more and capped with very low to low expansion potential fill. Details of the undercutting are provided in the Transition and Undercut Lot Details, Figure B of this document. In the event expansive soils are present near the ground surface, special design and construction considerations shall be utilized in general accordance with the recommendations of the geotechnical consultant. 5.5 Fill materials shall be moisture conditioned to near optimum moisture content prior to placement. The optimum moisture content will vary with material type and other factors. Moisture conditioning of fill soils shall be generally uniform throughout the soil mass. 5.6 Prior to placement of additional compacted fill material following a delay in the grading operations, the exposed surface of previously compacted fill shall be prepared to receive fill. Preparation may include scarifica- tion/ moisture conditioning, and recompaction. 5.7 Compacted fill shall be placed in horizontal lifts of approximately 8 inches in loose thickness. Prior to compaction, each lift shall be watered or dried as needed to achieve near optimum moisture condition, mixed, and then compacted by mechanical methods, using sheepsfoot rollers, multiple-wheel pneumatic-tired rollers, or other appropriate compacting rollers, to 90 percent or more of the specified maximum dry density. 5 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Uverpool Drive Typical Earthwork Guidelines Successive lifts shall be treated in a like manner until the desired finished grades are achieved. 5.8 Fill shall be tested in the field by the geotechnical consultant for evaluation of general compliance with the recommended relative compaction and moisture conditions. Field density testing shall conform to ASTM DI556-90 (Sand Cone method), D2937-83 (Drive-Cylinder method), and/or D2922-81 and D3017-88 (Nuclear Gauge method). Generally, one test shall be provided for approximately every 2 vertical feet of fill placed, or for approximately every 1000 cubic yards of fill placed. In addition, on slope faces one or more tests shall be taken for approximately every 10,000 square feet of slope face and/or approxi- mately every 10 vertical feet of slope height. Actual test intervals may vary as field conditions dictate. Fill found to be out of conformance with the grading recommendations shall be removed, moisture conditioned and compacted or otherwise handled to accomplish general compliance with the grading recommendations. 5.9 The contractor shall assist the geotechnical consultant by excavating suitable test pits for removal evaluation and/or for testing of compacted fill. 5.10 At the request of the geotechnical consultant, the contractor shall "shut down" or restrict grading equipment from operating in the area being tested to provide adequate testing time and safety for the field techni- cian. 5.11 The geotechnical consultant shall maintain a map with the approximate locations of field density tests. Unless the client provides for surveying of the test locations, the locations shown by the geotechnical consultant will be estimated. The geotechnical consultant shall not be held responsible for the accuracy of the horizontal or vertical control points. 5.12 Grading operations shall be performed under the observation of the geotechnical consultant. Testing and evaluation by the geotechnical consultant does not preclude the need for approval by or other require- ments of the jurisdictional agencies. 5.13 Fill materials shall not be placed, spread or compacted during unfavor- able weather conditions. When work is interrupted by heavy rains, the filling operation shall not be resumed until tests indicate that moisture content and density of the fill meet the project specifications. Regrading of the near-surface soil may be needed to achieve proper moisture content and density. 5.14 Upon completion of grading and termination of observation by the geotechnical consultant, no further filling or excavating, including that necessary for footings, foundations, retaining walls or other features, 6 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Liverpool Drive Typical Earthwork Guidelines shall be performed without the involvement of the geotechnical consul- tant. 5.15 Fill placed in areas not previously viewed and evaluated by the geotechnical consultant may have to be removed and recompacted at the contractor's expense. The depth and extent of removal of the unob- served and undocumented fill will be decided based upon review of the field conditions by the geotechnical consultant. 5.16 Off-site fill shall be treated in the same manner as recommended in these specifications for on-site fills. Off-site fill subdrains temporarily terminated (up gradient) shall be surveyed for future locating and connection. 5.17 Prior to placement of a canyon fill, a subdrain shall be installed in bedrock or compacted fill along the approximate aligrunent of the canyon bottom if recommended by the geotechnical consultant. Details of subdrain placement and configuration have been provided in the Canyon Subdrain Detail, Figure C, of this document. 5.18 Transition (cu1;lfill) lots shall generally be undercut 3 feet or more below finished grade to provide a generally uniform thickness of fill soil in the pad area. Where the depth of fill on a transition lot greatly exceeds 3 feet, overexcavation may be increased at the discretion of the geotech- nical consultant. Details of the undercut for transition lots are provided in the Transition and Undercut Lot Detail, Figure B, of this document. 6.0 OVERSIZED ROCK 6.1 During the course of grading operations, rocks or similar irreducible materials greater than 6 inches in dimension (oversized material) may be generated. These materials shall not be placed within the compacted fill unless placed in general accordance with the recommendations of the geotechnical consultant. 6.2 Where oversized rock (greater than 6 inches in dimension) or similar irreducible material is generated during grading, it is recommended, where practical, to waste such material off site, or on site in areas designated as "nonstructural rock disposal areas." Rock designated for disposal areas shall be placed with sufficient sandy soil to generally fill voids. The disposal area shall be capped with a 5-foot thickness of fill which is generally free of oversized material. 6.3 Rocks 6 inches in dimension and smaller may be utilized within the compacted fill, provided they are placed in such a manner that nesting of rock is reduced to acceptable levels. Fill shall be placed and compact- ed over and around the rock. The amount of rock greater than 3/4-inch 7 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 liverpool Drive Typical Earthwork Guidelines in dimension shall generally not exceed 40 percent of the total dry weight, unless the fill is specially designed and constructed as a "rock fill." 6.4 Rocks or similar irreducible materials greater than 6 inches but less than 4 feet in dimension generated during grading may be placed in windrows and capped with finer materials in accordance with the recommendations of the geotechnical consultant, the approval of the governing agencies, and the Oversized Rock Placement Detail, Figure 0, of this document. Selected native or imported granular soil (S.E. 30 or higher) shall be placed and flooded over and around the windrowed rock such that voids are filled. Windrows of oversized materials shall be staggered so that successive windrows of oversized materials are not in the same vertical plane. Rocks greater than 4 feet in dimension shall be broken down to 4 feet or smaller before placement, or they shall be disposed of off site. 7.0 SLOPES 7.1 Cut Slopes 7.1.1 Unless otherwise recommended by the geotechnical consultant and approved by the regulating agencies, permanent cut slopes shall not be steeper than 2:1 (horizontal to vertical). The maxi- mum recommended height of a cut slope shall be evaluated by the geotechnical consultant. Slopes in excess of 30 feet high shall be provided with terrace drains (swales) in accordance with the recommendations presented in the Uniform Building Code, Appendix A Chapter 33 and the details provided in Figure E. 7.1.2 The geotechnical consultant shall observe cut slopes during excavation. The geotechnical consultant shall be notified by the contractor prior to beginning slope excavations. 7.1.3 If excavations for cut slopes expose loose, cohesionless, signifi- cantly fractured or otherwise unsuitable materials, overexcavation of the unsuitable material and replacement with a compacted stabilization fill shall be evaluated and may be recommended by the geotechnical consultant. Unless otherwise specified by the geotechnical consultant, stabilization fill construction shall be in general accordance with the details provided on Figure F of this document. 7.1.4 If, during the course of grading, adverse or potentially adverse geotechnical conditions are encountered in the slope which were not anticipated in the preliminary evaluation report, the geotech- 8 I I I I I I I I I I I I I I I I I I I H'! Mr. Stephan A. Beck 405 Liverpool Drive Typical Earthwork Guidelines nieal consultant shall evaluate the conditions and provide appropriate recommendations. 7.2 Fill Slopes 7.2.1 When placing fill on slopes steeper than 5:1 (horizontal to vertical) topsoil, slope wash, colluvium, and other materials deemed unsuitable shall be removed. Near-horizontal keys and near-vertical benches shall be excavated into sound bedrock or firm fill material, in accordance with the recommendation of the geotechnical consultant. Keying and benching shall be accom- plished in general accordance with the details provided on Figure A of this document. Compacted fill shall not be placed in an area subsequent to keying and benching until the area has been observed by the geotechnical consultant. Where the natural gradient of a slope is less than 5:1, benching is generally not necessary. However, fill shall not be placed on compressible or otherwise unsuitable materials left on the slope face. 7.2.2 Within a single fill area where grading procedures dictate two or more separate fills, temporary slopes (false slopes) may be created. When placing fill adjacent to a temporary slope, benching shall be conducted in the manner described in Section 7.2.1. A 3-foot or higher near-vertical bench shall be excavated into the documented fill prior to placement of additional fill. 7.2.3 Unless otherwise recommended by the geotechnical consultant and approved by the regulating agencies, permanent fill slopes shall not be steeper than 2:1 (horizontal to vertical). The height of a fill slope shall be evaluated by the geotechnical consultant. Slopes in excess of 30 feet high shall be provided with terrace drains (swales) and backdrains in accordance with the recommendations presented in the Uniform Building Code, Appendix A Chapter 33 and the details provided in Figure E of this document. 7.2.4 Unless specifically recommended otherwise, compacted fill slopes shall be overbuilt and cut back to grade, exposing firm compacted fill. The actual amount of overbuilding may vary as field conditions dictate. If the desired results are not achieved, the existing slopes shall be overexcavated and reconstructed in accordance with the recommendations of the geotechnical consul- tant. The degree of overbuilding may be increased until the desired compacted slope face condition is achieved. Care shall be taken by the contractor to provide mechanical compaction as close to the outer edge of the overbuilt slope surface as practical. 9 I I I I I I I I I I I I I I I I I I I II~III Mr. Stephan A. Beck 405 Ilverpool Drive Typical Earthwork Guidelines 7.2.5 If access restrictions, property line location or other constraints prevent overbuilding and cutting back of the slope face, an alternative method for compaction of the slope face may be attempted by conventional construction procedures including backrolling at intervals of 4 feet or less in vertical slope height, or as dictated by the capability of the available equipment, which ever is less. Fill slopes shall be backrolled utilizing a conventional sheepsfoot-type roller. Care shall be taken to maintain the desired moisture conditions and/or reestablish the same, as needed, prior to backrolling. Upon achieving final grade, the slope shall again be moisture conditioned and backrolled. 7.2.6 The placement, moisture conditioning and compaction of fill slope materials shall be done in accordance with the recom- mendations presented in Section 5.0 of this document. 7.2.7 The contractor shall be ultimately responsible for placing and compacting the soil to obtain a relative compaction of 90 percent or more of the maximum dry density and a moisture content in accordance with Section 5.0 out to the slope face. The geotechnical consultant shall perform moisture and density tests at intervals of one test for approximately every 10,000 square feet of slope face and/or approximately every 10 feet of vertical height of slope. 7.2.8 Backdrains shall be provided in fill slopes in accordance with the details presented on Figure A of this document, or as recom- mended by the geotechnical consultant. 7.2.9 Fill shall be compacted prior to placement of survey stakes. This is particularly important on fill slopes. Slope stakes shall not be placed until the slope is compacted and tested. If a slope face fill does not meet the recommendations presented in this specifica- tion, it shall be recognized that stakes placed prior to completion of the recompaction effort will be removed and/or demolished at such time as the compaction procedures resume. 7.3 Top-of-Slope Drainage 7.3.1 For pad areas above slopes, positive drainage shall be established away from the top of slope. This may be accomplished utilizing a berm and pad gradient of 2 percent or steeper at the top-of- slope areas. Site runoff shall not be permitted to flow over the tops of slopes. 10 I I I I I I I I I I I I I I I I I I I ii' Mr. Stephan A. Beck 405 Liverpool Drive Typical Earthwork Guidelines 7.3.2 Gunite-lined brow ditches shall be placed at the top of cut slopes to redirect surface runoff where drainage devices are not otherwise provided. 7.4 Slope Maintenance 7.4.1 In order to enhance surficial slope stability, slope planting shall be accomplished at the completion of grading. Slope plants shall consist of deep-rooting, drought-tolerant vegetation. Native vegetation is generally desirable. Plants native to semi-arid and arid areas may also be appropriate. A landscape architect shall be consulted regarding the actual types of plants and planting configuration to be used. 7.4.2 Irrigation pipes shall be anchored to slope faces and not placed in trenches excavated into slope faces. Slope irrigation shall be maintained at a level just sufficient to support plant growth. Property owners shall be made aware that overwatering of slopes is detrimental to slope stability. Slopes shall be monitored regularly and broken sprinkler heads and/or pipes shall be repaired immediately. 7.4.3 Periodic observation of landscaped slope areas shall be planned and appropriate measures taken to enhance growth of landscape plants. 7.4.4 Graded swales at the top of slopes and terrace drains shall be installed and the property owners notified that the drains shall be periodically checked so that they may be kept clear. Damage to drainage improvements .shall be repaired immediately. To reduce siltation, terrace drains shall be constructed at a gradient of 3 percent or steeper, in aq:ordance with the recommendations of the project civil engineer. 7.4.5 If slope failures occur, the geotechnical consultant shall be contacted immediately for field review of site conditions and development of recommendations for evaluation and repair. 8.0 TRENCH BACKFILL 8.1 Trench backfill shall consist of granular soils from the trench bottom to 1 foot above the pipe. On-site or imported fill which has been evaluated by the geotechnical consultant may be used above the granular backfill. The cover soils directly in contact with the pipe shall be classified as having a very low expansion potential, in accordance with UBC 18-2, 11 I I I I I I I I I I I I I I I I I I I 'II III Mr. Stephan A. Beck 405 Uverpool Drive Typical Earthwork Guidelines and shall contain no rocks or ch diameter. of hard soil larger than 3/4-inch in 8.2 Trench backfill shall, unless othe 'se recommended, be compacted by mechanical means to 90 percent r more of maximum dry density as evaluated in accordance with AS D1557-91. Backfill soils shall be placed in loose lifts 8-inches thick r thinner, moisture conditioned, and compacted in accordance with t recommendations of Section 5.0 of this document. The backfill shall e tested by the geotechnical consul- tant at vertical intervals of appro' ately 2 feet of backfill placed and at spacings along the trench of appr ximately 100 feet in the same lift. 8.3 Jetting of trench backfill materi method of densification, unless t draining and provisions have bee water utilized in the jetting pr geotechnical consultant shall eval backfill may be jetted in place. is generally not a recommended e on-site soils are sufficiently free- ade for adequate dissipation of the ess. If jetting is to be used, the te and indicate areas where trench 8.4 If it is decided that jetting may be equivalent greater than 30 shall be jetted. Jetting shall generally b narrower in width and 4 feet or s operations, trench backfill shall grade. . . zed, granular material with a sand ed for backfilling in the areas to be considered for trenches 2 feet or allower in depth. Following jetting mechanically compacted to finish 8.5 Trench backfill which underlies t e zone of influence of foundations shall be mechanically compacted t 90 percent or more of maximum dry density, as evaluated in accordanc with ASTM D1557-91. The zone of influence of the foundations is generally defined as the roughly triangular area within the limits 0 a 1:1 projection from the inner and outer edges of the foundation, proj cted down and out from both edges. 8.6 Trench backfill within slab areas means to a relative compaction of density, as evaluated in accordan interior trenches, density testing performed, deemed appropriate b hall be compacted by mechanical o percent or more of maximum dry with ASTM 01557-91. For minor y be omitted or spot testing may be the geotechnical consultant. 8.7 When compacting soil in close pr ximity to utilities, care shall be taken by the grading contractor so thatechanical methods used to compact the soils do not damage the utilitis. If the utility contractors indicate that it is undesirable to use compa 'on equipment in close proximity to a buried conduit, then the gradig contractor may elect to use light mechanical compaction equipment (lr, with the approval of the geotech- nical consultant, cover the conduit With clean granular material. These granular materials shall be jetted iii place to the top of the conduit in accordance with the recommenda 'pns of Section 8.4 prior to initiating 12 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Uverpool Drive 8.9 mechanical compaction proced compaction may also be approp consultant at the time of constru 8.8 Clean granular backfill and/or be for use in slope areas unless pro to mitigate the potential for b backfill materials. The contractor shall exercise th cautions, in accordance with OS conducting trenching operations. laying back trench excavations a type, for trenches in excess of consultant is not responsible fo stability of the trenches. 9.0 DRAINAGE 9.1 9.2 9.3 9.4 Canyon subdrain systems recom shall be installed in accordance Figure D, provided in this do installed to conform to the appro project plans. The actual subdr . geotechnical consultant in the fiel in the attached Canyon Subdr modified unless so recommen Subdrains shall be surveyed by a for line and grade after installatio the surveys prior to commencem Typical backdrains for stability, si installed in accordance with the Figure F of this document. !~ Typical Earthwork Guidelines . Other methods of utility trench e, upon review by the geotechnical n. g materials are not recommended ns are made for a drainage system p of seepage forces or piping of I ecessary and required safety pre- Trench Safety Regulations, while uch precautions include shoring or 1 or flatter, depending on material feet in depth. The geotechnical he safety of trench operations or ded by the geotechnical consultant 'th the Canyon Subdrain Detail, ent. Canyon subdrains shall be ate alignment and details shown on location shall be evaluated by the uring grading. Materials specified Detail shall not be changed or by the geotechnical consultant. ensed land surveyor/civil engineer Sufficient time shall be allowed for of filling over the subdrains. e hill, and shear key fills shall be etails provided on Figure A and Roof, pad, and slope drainage sh' be directed away from slopes and structures to suitable discharge I eas by nonerodible devices (e.g., gutters, downspouts, concrete sw , etc.). Positive drainage adjacent to stru" I es shall be established and main- tained. Positive drainage may be 'complished by providing drainage away from the foundations of the cture at a gradient of 2 percent or steeper for a distance of 5 feet or I re outside the building perimeter, further maintained by a graded s ,e leading to an appropriate outlet, in accordance with the recomme tions of the project civil engineer and/or landscape architect. 13 I I I I I I I I I I I I I I I I I I I 1111' Mr. Stephan A. Beck 405 Uverpool Drive Typical Earthwork Guidelines 9.5 Surface drainage on the site sh be provided so that water is not permitted to pond. A gradient 0 2 percent or steeper shall be main- tained over the pad area and dr age patterns shall be established to direct and remove water from th site to an appropriate outlet. 9.6 Care shall be taken by the contra or during final grading to preserve any berms, drainage terraces, i erceptor swales or other drainage devices of a permanent nature on r adjacent to the property. Drainage patterns established at the time of "nal grading shall be maintained for the life of the project. Property 0 ers shall be made very clearly aware that altering drainage patterns ma be detrimental to slope stability and foundation performance. 10.0 SITE PROTECTION 10.1 Protection of the site during the p "od of grading shall be the responsi- bility of the contractor unless othe provisions are made in writing and agreed upon among the concerne parties. Completion of a portion of the project shall not be considere to preclude that portion or adjacent areas from the need for site prote . on, until such time as the project is complete as agreed upon by the g technical consultant, the client, and the regulatory agency. 10.2 The contractor is responsible for t stability of temporary excavations. Recommendations by the geotec .cal consultant pertaining to tempo- rary excavations are made in consi eration of stability of the completed project and, therefore, shall not be onsidered to preclude the responsi- bilities of the contractor. Rec mendations by the geotechnical consultant shall also not be cons ered to preclude more restrictive requirements by the applicable re atory agencies. 10.3 Precautions shall be taken durin the performance of site clearing, excavation, and grading to prote the site from flooding, ponding, or inundation by surface runoff. T porary provisions shall be made during the rainy season to adequa ly direct surface runoff away from and off the working site. Where I w areas cannot be avoided, pumps shall be provided to remove water s needed during periods of rainfall. 10.4 During periods of rainfall, plastic reduce the potential for unprotecte needed, the contractor shall install sandbags or other appropriate devi provide safe conditions during in eeting shall be used as needed to slopes to become saturated. Where heck dams, desilting basins, riprap, s or methods to reduce erosion and ment weather. 10.5 During periods of rainfall, the g technical consultant shall be kept informed by the contractor of the ature of remedial or precautionary 14 !I illl I Mr. Stephan A. Beck Typical Earthwork Guidelines 405 Uverpool Drive I work being performed on site (e. pumping, placement of sandbags or I plastic sheeting, other labor, do g, etc.). 10.6 Following periods of rainfall, the tractor shall contact the geotechnical I consultant and arrange a walk-o of the site in order to visually assess rain-related damage. The geotec 'cal consultant may also recommend excavation and testing in order aid in its evaluation. At the request I of the geotechnical consultant, t contractor shall make excavations in order to aid in evaluation of the tent of rain-related damage. I 10.7 Rain- or irrigation-related dama shall be considered to include, but may not be limited to, erosion, ting, saturation, swelling, structural distress, and other adverse con . ons identified by the geotechnical I consultant. Soil adversely affe d shall be classified as ''Unsuitable Material" and shall be subject to erexcavation and replacement with compacted fill or to other reme grading as recommended by the I geotechnical consultant. 10.8 Relatively level areas where satur d soils and/or erosion gullies exist to I depths greater than 1 foot shall b verexcavated to competent materials as evaluated by the geotechnical nsultant. Where adverse conditions extend to less than 1 foot in de , saturated and/or eroded materials I may be processed in-place. erexcavated or in-place processed materials shall be moisture con . oned and compacted in accordance with the recommendations provi in Section S.D. If the desired results I are not achieved, the affected ma . als shall be overexcavated, moisture conditioned, and compacted un he specifications are met. I 10.9 Slope areas where saturated soil d/or erosion gullies exist to depths greater than 1 foot shall be overe vated and replaced as compacted fill in accordance with the applica specifications. Where adversely I affected materials exist to dep of 1 foot or less below proposed finished grade, remedial grading moisture conditioning in-place and compaction in accordance with appropriate specifications may be I attempted. If the desired results not achieved, the affected materials shall be overexcavated, moisture nditioned, and compacted until the specifications are met. As condi . ns dictate, other slope repair proce- I dures may also be recommende y the geotechnical consultant. 10.10 During construction, the contr r shall grade the site to provide I positive drainage away from stru es and to keep water from ponding adjacent to structures. Water sh not be allowed to damage adjacent properties. Positive drainage sh e maintained by the contractor until I permanent drainage and erosion ucing devices are installed in accor- dance with project plans. I I 15 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Liverpool Drive ~ Typical Earthwork Guidelines 11.0 DEFINITIONS OF TERMS ALLUVIUM: AS-GRADED (AS-BUILT): BACKCUT: BACKDRAIN: BEDROCK: BENCH: Unconsolidate water; include canyons, flood and in estuarie etrital deposits deposited by flowing ediments deposited in river beds, , lakes, fans at the foot of slopes, s upon completion of grading. Generally a system placed as buttresses, s bed in-place rock, either at the surficial deposits of soil. A relatively leve tep and near-vertical riser excavated into sloping gr d on which fill is to be placed. BORROW (IMPORT): Any fill materi auled to the project site from off-site areas. BUlTRESS FILL: CIVIL ENGINEER: CLIENT: COLLUVIUM: A fill mass, the engineering cal adverse geolo specified by mi maximum back tains a back dr nfiguration of which is designed by ations, to retain slopes containing features. A buttress is generally um key width and depth and by t angle. A buttress normally con- age system. The Registered responsible for surveying, an conditions. ivil Engineer or consulting firm eparation of the grading plans and verifying as-graded topographic The developer rized represent of reviewing th by the geotec contractor an~ and/or provide his/her project-responsible autho- e. The client has the responsibility ndings and recommendations made al consultant and authorizing the other consultants to perform work ices. Generally loose near the base 0 posits, usually found on the face or lopes and brought there chiefly by 16 I' I Mr. Stephan A. Beck Typical Earthwork Guidelines 405 Iiverpool Drive I gravity throu low continuous downhill creep (see I also Slope Was COMPACTION: The densificati of a fill by mechanical means. I CONTRACTOR: A person or c pany under contract or otherwise retained by the . ent to perform demolition, grading, I and other site . provements. DEBRIS: The products 0 eating, grubbing, and/or demolition, I or contaminate oil material unsuitable for reuse as compacted fill, d/or any other material so desig- nated by the g echnical consultant. I ENGINEERED FILL: A fill which t geotechnical consultant or his/her representative s observed and/or tested during I placement, ena ng him to conclude that the fill has been placed i substantial compliance with the recommendati of the geotechnical consultant and I the governing ncy requirements. ENGINEERING I GEOLOGIST: A geologist ce d by the state licensing agency who applies geolo knowledge and principles to the exploration an aluation of naturally occurring rock I and soil, as rel d to the design of civil works. EROSION: The wearing a of the ground surface as a result of I the movement wind, water, and/or ice. EXCAVATION: The mechanic moval of earth materials. I EXISTING GRADE: The ground s ce configuration prior to grading; original grade. I FILL: Any deposit of il, rock, soil-rock blends, or other similar material laced by man. I FINISH GRADE: The as-graded und surface elevation. I GEOFABRIC: An engineering tile utilized in geotechnical applica- tions such as s ade stabilization and filtering. I GEOTECHNICAL CONSULTANT: The geotechnic ngineering and engineering geology consulting firm tained to provide technical services I for the proj ect. or the purpose of these specifica- tions, observati by the geotechnical consultant I 17 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Liverpool Drive GEOTECHNICAL ENGINEER: GRADING: include obse engineering ge and responsibl A licensed civil proved by the scientific meth sional experie and use of kno to the resoluti nical enginee . ing aspects of s geophysics, hy Any operation combinations t LANDSLIDE DEBRIS: Material, often from instability MAXIMUM DRY DENSITY: OPTIMUM MOISTURE: RELATIVE COMPACTION: ROUGH GRADE: SHEAR KEY: SITE: Standard labo weight. Unless unit weight s ASTM Test Me The moisture c The degree of c of a material a weight of the The ground s surface elevati approved plan. Similar to a sub ly constructed slope in order slope without the slope. The particular performed. 18 !;l Typical Earthwork Guidelines ons by the geotechnical engineer, gist and other persons employed by o the geotechnical consultant. gineer or geotechnical engineer, ap- te licensing agency, who applies , engineering principles, and profes- to the acquisition, interpretation, dge of materials of the earth's crust of engineering problems. Geotech- encompasses many of the engineer- echanics, rock mechanics, geology, logy, and related sciences. nsisting of excavation, filling, or eof and associated operations. rous and of low density, produced natural or manmade slopes. ory test for maximum dry unit erwise specified, the maximum dry be evaluated in accordance with d 01557-91. tent at the maximum density. paction (expressed as a percentage) mpared to the maximum dry unit erial. ce configuration at which time the approximately conform to the face buttress; however, it is general- excavating a slot within a natural stabilize the upper portion of the oaching into the lower portion of cel of land where grading is being I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Ilverpool Drive SLOPE: SLOPE WASH: SLOUGH: SOIL: STABILIZATION FILL: SUBDRAIN: TAILINGS: TERRACE: TOPSOIL: WINDROW: An inclined gro generally sp vertical units. Soil and/or roc down a slope water not confi Loose, uncom grading operati Naturallyoc combinations t A fill mass, th related to slop dards of practic adverse conditi normallyspeci and by maxim mayor may no fied. Generally a p system placed buried canyons Non-engineere to equipment h A relatively lev graded slope s nance purposes The presumabl materials, whic contains organi A row of large accordance wi nical Consultan 19 II: Typical Earthwork Guidelines d surface, the steepness of which is d as a ratio of horizontal units to material that has been transported gravity assisted by the action of d to channels (see also Colluvium). fill material generated during g deposits of sand, silt, clay, etc., or reof. configuration of which is typically eight and is specified by the stan- for enhancing the stability of locally s. A minimum stabilization fill is by minimum key width and depth backcut angle. A stabilization fill have a back drainage system speci- e-and-gravel or similar drainage neath a fill along the alignment of r former drainage channels. which accumulates on or adjacent -roads. bench constructed on the face of a ce for drainage control and mainte- ertile upper zone of soil or bedrock is usually dark in color, loose, and aterials. ks buried within engineered fill in . delines set forth by the Geotech- I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Uverpool Drive Typical Earthwork Guidelines and shall contain no rocks or chunks of hard soil larger than 3/4-inch in diameter. 8.2 Trench backfill shall, unless otherwise recommended, be compacted by mechanical means to 90 percent or more of maximum dry density as evaluated in accordance with AS1M D1557-91. Backfill soils shall be placed in loose lifts S-inches thick or thinner, moisture conditioned, and compacted in accordance with the recommendations of Section 5.0 of this document. The backfill shall be tested by the geotechnical consul- tant at vertical intervals of approximately 2 feet of backfill placed and at spacings along the trench of approximately 100 feet in the same lift. 8.3 Jetting of trench backfill materials is generally not a recommended method of densification, unless the on-site soils are sufficiently free- draining and provisions have been made for adequate dissipation of the water utilized in the jetting process. If jetting is to be used, the geotechnical consultant shall evaluate and indicate areas where trench backfill may be jetted in place. 8.4 If it is decided that jetting may be uti1ized, granular material with a sand equivalent greater than 30 shall be used for backfil1ing in the areas to be jetted. Jetting shall generally be considered for trenches 2 feet or narrower in width and 4 feet or shallower in depth. Following jetting operations, trench backfill shall be mechanically compacted to finish grade. 8.5 Trench backfill which underlies the zone of influence of foundations shall be mechanically compacted to 90 percent or more of maximum dry density, as evaluated in accordance with AS1M D1557-91. The zone of influence of the foundations is generally defined as the roughly triangular area within the limits of a 1:1 projection from the inner and outer edges of the foundation, projected down and out from both edges. 8.6 Trench backfill within slab areas shall be compacted by mechanical means to a relative compaction of 90 percent or more of maximum dry density, as evaluated in accordance with AS1M D1557-91. For minor interior trenches, density testing may be omitted or spot testing may be performed, deemed appropriate by the geotechnical consultant. 8.7 When compacting soil in close proximity to utilities, care shall be taken by the grading contractor so that mechanical methods used to compact the soils do not damage the utilities. If the utility contractors indicate that it is undesirable to use compaction equipment in close proximity to a buried conduit, then the grading contractor may elect to use light mechanical compaction equipment or, with the approval of the geotech- nical consultant, cover the conduit with clean granular material. These granular materials shall be jetted in place to the top of the conduit in accordance with the recommendations of Section 8.4 prior to initiating 12 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Liverpool Drive Typical Earthwork Guidelines mechanical compaction procedures. Other methods of utility trench compaction may also be appropriate, upon review by the geotechnical consultant at the time of construction. 8.8 Clean granular backfi11 and/or bedding materials are not recommended for use in slope areas unless provisions are made for a drainage system to mitigate the potential for buildup of seepage forces or piping of backfi11 materials. 8.9 The contractor shall exercise the necessary and required safety pre- cautions, in accordance with OSHA Trench Safety Regulations, while conducting trenching operations. Such precautions include shoring or laying back trench excavations at 1:1 or flatter, depending on material type, for trenches in excess of 5 feet in depth. The geotechnical consultant is not responsible for the safety of trench operations or stability of the trenches. 9.0 DRAINAGE 9.1 Canyon subdrain systems recommended by the geotechnical consultant shall be installed in accordance with the Canyon Subdrain Detail, Figure D, provided in this document. Canyon subdrains shall be installed to conform to the approximate alignment and details shown on project plans. The actual subdrain location shall be evaluated by the geotechnical consultant in the field during grading. Materials specified in the attached Canyon Subdrain Detail shall not be changed or modified unless so recommended by the geotechnical consultant. Subdrains shall be surveyed by a licensed land surveyor/civil engineer for line and grade after installation. Sufficient time shall be allowed for the surveys prior to commencement of filling over the subdrains. 9.2 Typical backdrains for stability, side hill, and shear key fills shall be installed in accordance with the details provided on Figure A and Figure F of this document. 9.3 Roof, pad, and slope drainage shall be directed away from slopes and structures to suitable discharge areas by nonerodible devices (e.g., gutters, downspouts, concrete swales, etc.). 9.4 Positive drainage adjacent to structures shall be established and main- tained. Positive drainage may be accomplished by providing drainage away from the foundations of the structure at a gradient of 2 percent or steeper for a distance of 5 feet or more outside the building perimeter, further maintained by a graded swale leading to an appropriate outlet, in accordance with the recommendations of the project civil engineer and/or landscape architect. 13 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Uverpool Drive Typical Earthwork Guidelines 9.5 Surface drainage on the site shall be provided so that water is not permitted to pond. A gradient of 2 percent or steeper shall be main- tained over the pad area and drainage patterns shall be established to direct and remove water from the site to an appropriate outlet. 9.6 Care shall be taken by the contractor during final grading to preserve any berms, drainage terraces, interceptor swales or other drainage devices of a permanent nature on or adjacent to the property. Drainage patterns established at the time of final grading shall be maintained for the life of the project. Property owners shall be made very clearly aware that altering drainage patterns may be detrimental to slope stability and foundation performance. 10.0 SITE PROTECTION 10.1 Protection of the site during the period of grading shall be the responsi- bility of the contractor unless other provisions are made in writing and agreed upon among the concerned parties. Completion of a portion of the project shall not be considered to preclude that portion or adjacent areas from the need for site protection, until such time as the project is complete as agreed upon by the geotechnical consultant, the client, and the regulatory agency. 10.2 The contractor is responsible for the stability of temporary excavations. Recommendations by the geotechnical consultant pertaining to tempo- rary excavations are made in consideration of stability of the completed project and, therefore, shall not be considered to preclude the responsi- bilities of the contractor. Recommendations by the geotechnical consultant shall also not be considered to preclude more restrictive requirements by the applicable regulatory agencies. 10.3 Precautions shall be taken during the performance of site clearing, excavation, and grading to protect the site from flooding, ponding, or inundation by surface runoff. Temporary provisions shall be made during the rainy season to adequately direct surface runoff away from and off the working site. Where low areas cannot be avoided, pumps shall be provided to remove water as needed during periods of rainfall. 10.4 During periods of rainfall, plastic sheeting shall be used as needed to reduce the potential for unprotected slopes to become saturated. Where needed, the contractor shall install check dams, de silting basins, riprap, sandbags or other appropriate devices or methods to reduce erosion and provide safe conditions during inclement weather. 10.5 During periods of rainfall, the geotechnical consultant shall be kept informed by the contractor of the nature of remedial or precautionary 14 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Iiverpool Drive Typical Earthwork Guidelines work being performed on site (e.g., pumping, placement of sandbags or plastic sheeting, other labor, dozing, etc.). 10.6 Following periods of rainfall, the contractor shall contact the geotechnical consultant and arrange a walk-over of the site in order to visually assess rain-related damage. The geotechnical consultant may also recommend excavation and testing in order to aid in its evaluation. At the request of the geotechnical consultant, the contractor shall make excavations in order to aid in evaluation of the extent of rain-related damage. 10.7 Rain- or irrigation-related damage shall be considered to include, but may not be limited to, erosion, silting, saturation, swelling, structural distress, and other adverse conditions identified by the geotechnical consultant. Soil adversely affected shall be classified as "Unsuitable Material" and shall be subject to overexcavation and replacement with compacted fill or to other remedial grading as recommended by the geotechnical consultant. 10.8 Relatively level areas where saturated soils and/or erosion gullies exist to depths greater than 1 foot shall be overexcavated to competent materials as evaluated by the geotechnical consultant. Where adverse conditions extend to less than 1 foot in depth, saturated and/or eroded materials may be processed in-place. Overexcavated or in-place processed materials shall be moisture conditioned and compacted in accordance with the recommendations provided in Section 5.0. If the desired results are not achieved, the affected materials shall be overexcavated, moisture conditioned, and compacted until the specifications are met. 10.9 Slope areas where saturated soil and/or erosion gullies exist to depths greater than 1 foot shall be overexcavated and replaced as compacted fill in accordance with the applicable specifications. Where adversely affected materials exist to depths of 1 foot or less below proposed finished grade, remedial grading by moisture conditioning in-place and compaction in accordance with the appropriate specifications may be attempted. If the desired results are not achieved, the affected materials shall be overexcavated, moisture conditioned, and compacted until the specifications are met. As conditions dictate, other slope repair proce- dures may also be recommended by the geotechnical consultant. 10.10 During construction, the contractor shall grade the site to provide positive drainage away from structures and to keep water from ponding adjacent to structures. Water shall not be allowed to damage adjacent properties. Positive drainage shall be maintained by the contractor until permanent drainage and erosion reducing devices are installed in accor- dance with project plans. 15 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Liverpool Drive Typical Earthwork Guidelines 11.0 DEFINITIONS OF TERMS ALLUVIUM: Unconsolidated detrital deposits deposited by flowing water; includes sediments deposited in river beds, canyons, flood plains, lakes, fans at the foot of slopes, and in estuaries. AS-GRADED (AS-BUILT): The site conditions upon completion of grading. BACKCUT: A temporary construction slope at the rear of earth- retaining structures such as buttresses, shear keys, stabilization fills, or retaining walls. BACKDRAIN: Generally a pipe-and-gravel or similar drainage system placed behind earth-retaining structures such as buttresses, stabilization fills, and retaining walls. BEDROCK: Relatively undisturbed in-place rock, either at the surface or beneath surficial deposits of soil. BENCH: A relatively level step and near-vertical riser excavated into sloping ground on which fill is to be placed. BORROW (IMPORT): Any fill material hauled to the project site from off-site areas. BUlTRESS FILL: A fill mass, the configuration of which is designed by engineering calculations, to retain slopes containing adverse geologic features. A buttress is generally specified by minimum key width and depth and by maximum backcut angle. A buttress normally con- tains a back drainage system. CIVIL ENGINEER: The Registered Civil Engineer or consulting firm responsible for preparation of the grading plans and surveying, and verifying as-graded topographic conditions. CLIENT: The developer or his/her project-responsible autho- rized representative. The client has the responsibility of reviewing the findings and recommendations made by the geotechnical consultant and authorizing the contractor and/or other consultants to perform work and/or provide services. COLLUVIUM: Generally loose deposits, usually found on the face or near the base of slopes and brought there chiefly by 16 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Liverpool Drive COMPACfION: CONTRACfOR: DEBRIS: ENGINEERED FILL: ENGINEERING GEOLOGIST: EROSION: EXCAVATION: EXISTING GRADE: FILL: FINISH GRADE: GEOFABRIC: GEOTECHNICAL CONSULTANT: Typical Earthwork Guidelines gravity through slow continuous downhill creep (see also Slope Wash). The densification of a fill by mechanical means. A person or company under contract or otherwise retained by the client to perform demolition, grading, and other site improvements. The products of clearing, grubbing, and/or demolition, or contaminated soil material unsuitable for reuse as compacted fill, and/or any other material so desig- nated by the geotechnical consultant. A fill which the geotechnical consultant or his/her representative has observed and/or tested during placement, enabling him to conclude that the fill has been placed in substantial compliance with the recommendations of the geotechnical consultant and the governing agency requirements. A geologist certified by the state licensing agency who applies geologic knowledge and principles to the exploration and evaluation of naturally occurring rock and soil, as related to the design of civil works. The wearing away of the ground surface as a result of the movement of wind, water, and/or ice. The mechanical removal of earth materials. The ground surface configuration prior to grading; original grade. Any deposit of soil, rock, soil-rock blends, or other similar materials placed by man. The as-graded ground surface elevation. An engineering textile utilized in geotechnical applica- tions such as sub grade stabilization and filtering. The geotechnical engineering and engineering geology consulting firm retained to provide technical services for the project. For the purpose of these specifica- tions, observations by the geotechnical consultant 17 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Uverpool Drive GEOTECHNICAL ENGINEER: GRADING: Typical Earthwork Guidelines include observations by the geotechnical engineer, engineering geologist and other persons employed by and responsible to the geotechnical consultant. A licensed civil engineer or geotechnical engineer, ap- proved by the state licensing agency, who applies scientific methods, engineering principles, and profes- sional experience to the acquisition, interpretation, and use of knowledge of materials of the earth's crust to the resolution of engineering problems. Geotech- nical engineering encompasses many of the engineer- ing aspects of soil mechanics, rock mechanics, geology, geophysics, hydrology, and related sciences. Any operation consisting of excavation, filling, or combinations thereof and associated operations. LANDSLIDE DEBRIS: Material, often porous and of low density, produced from instability of natural or manrnade slopes. MAXIMUM DRY DENSITY: OPTIMUM MOISTURE: RELATIVE COMPACTION: ROUGH GRADE: SHEAR KEY: SITE: Standard laboratory test for maximum dry unit weight. Unless otherwise specified, the maximum dry unit weight shall be evaluated in accordance with ASTM Test Method 01557-91. The moisture content at the maximum density. The degree of compaction (expressed as a percentage) of a material as compared to the maximum dry unit weight of the material. The ground surface configuration at which time the surface elevations approximately conform to the approved plan. Similar to a subsurface buttress; however, it is general- ly constructed by excavating a slot within a natural slope in order to stabilize the upper portion of the slope without encroaching into the lower portion of the slope. The particular parcel of land where grading is being performed. 18 I I I I I I I I I I I I I I I I I I I Mr. Stephan A. Beck 405 Iiverpool Drive SLOPE: SLOPE WASH: SLOUGH: SOIL: ST ABILIZA nON FILL: SUBDRAIN: TAILINGS: TERRACE: TOPSOIL: WINDROW: Typical Earthwork Guidelines An inclined ground surface, the steepness of which is generally specified as a ratio of horizontal units to vertical units. Soil and/or rock material that has been transported down a slope by gravity assisted by the action of water not confined to channels (see also Colluvium). Loose, uncompacted fill material generated during grading operations. Naturally occurring deposits of sand, silt, clay, etc., or combinations thereof. A fill mass, the configuration of which is typically related to slope height and is specified by the stan- dards of practice for enhancing the stability of locally adverse conditions. A minimum stabilization fill is normally specified by minimum key width and depth and by maximum backcut angle. A stabilization fill mayor may not have a back drainage system speci- fied. Generally a pipe-and-gravel or similar drainage system placed beneath a fill along the alignment of buried canyons or former drainage channels. Non-engineered fill which accumulates on or adjacent to equipment haul-roads. A relatively level bench constructed on the face of a graded slope surface for drainage control and mainte- nance purposes. The presumably fertile upper zone of soil or bedrock materials, which is usually dark in color, loose, and contains organic materials. A row of large rocks buried within engineered fill in accordance with guidelines set forth by the Geotech- nical Consultant. 19