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1991-1133 C/T GEOTECHNICAL INVESTIGATION Encinitas Villas �- 760, 800, 820 Encinitas Blvd. Encinitas, CA. FEB 2 7 1991 CITY OF ENCINITAS DEPT. OF PUBLIC WORKS Prepared for: Silldorf, Burdman, Duignan a Eisenberg March 21, 1989 _ �ddIlGRom 0 m o _ 9 GEOTECHNICAL CONSULTANTS March 21, 1989 Mr. Scott A. Burdman, Esq. Silldorf, Burdman, Duignan & Eisenberg 1810 State Street 21- 0389 -D1 San Diego, CA 92101 -2514 SUBJECT: GEOTECHNICAL INVESTIGATION ENCINITAS VILLAS 760, 800 AND 820 ENCINITAS BOULEVARD ENCINITAS, CALIFORNIA Dear Mr. Burdman: In accordance with your request and our agreement, this office has completed geotechnical studies of selected units within the subject property. The site is a condominium development including 34 dwelling units within three separate two -story buildings. We understand that distressed structures are reported, primarily in the central areas of the development. Our scope of work has included the determination of the geotechnical conditions beneath the development and their impact upon the noted distress. Site conditions at the project are depicted on a Site Plan enclosed with this transmittal as Plate 1. The plan also presents pertinent field data obtained during this study. 1 SITE INVESTIGATION Research Geotechnical conditions at the study site were determined from an initial research into available technical data including recorded maps on file with the County of San Diego. The following documents were obtained and reviewed in support of this investigation: -- 1. List of complaints submitted by owner /occupants of dwelling units at Encinitas Villas. 2. County of San Diego Tentative Tract Map 3782 (Map No. 9317). 3. As -Built Map for the improvement of Encinitas Blvd., approved June 1, 1978 (reproduced and enclosed herein as Plate 13). 4. Soils Investigation Report, Encinitas Villas, prepared by Benton Engineering, Inc., dated March 29, 1984. 5. Preliminary Investigation Report, Encinitas Villas, prepared by Impact General, Inc., dated November 9, 1988. Field Study -- Field conditions at the property were determined from the following work: a) The excavation of large and small diameter test borings Large diameter borings were entered and carefully down - hole logged by our project geologist who also performed 6 -inch diameter sand cone density tests on the upper soil deposits. Below, 2 1/2 inch diameter ring samples were driven into the exposed soils and retained for laboratory testing. Bulk samples were retained from the borings at frequent intervals. 2 Six -inch diameter borings were utilized chiefly for standard penetration tests. These were performed at frequent intervals extending to depths of 40 feet where dense soil/ rock units were encountered. Boring locations at the property are shown on Plate 1. Logs of the borings are attached as Plates 15 - 17. b) Hand - excavated test pits were utilized to expose exterior __. foundation conditions of Buildings 800 and 820. A limited section of the foundation was exposed and measured by our project geologist. The location of the test pits is shown on Plate 1. Logs of the pits are enclosed as Plates 18 - 19. C) Manometer (water- level) surveys were conducted across interior floor surfaces of seven lower units in the central areas of the project. The surveys utilize a water -level device which records very small distortions in a relatively -- flat surface. Field data is processed by a computer and plotted as lines of equal elevation. A 3- dimensional graphic display with exaggerated vertical scale is also provided. At the time of the survey, selected floor surfaces were inspected by removing carpets adjacent to north -south walls in the rear portion of the dwellings whenever possible. Floor cracks during the survey work are depicted on Plate 1 and the enclosed Manometer Survey Result Sheets, Plates 5 - 12. 3 d) Laboratory Tests Representative samples of the underlying soil /rock units at the property were obtained from the boring excavations for laboratory testing. Bulk and relatively undisturbed samples were retained and transported to the laboratory in moisture resistant containers. The following tests were performed: Density Tests Field density tests were performed on fill and natural soil deposits in Test Borings 1, 2, and 3. In borings 1 and 2, sand cone tests were taken at 3 foot vertical intervals. one 4 -inch drive cylinder density test was taken in Boring 2 at a depth of nine feet. -- Additionally, 2 3/8 -inch drive ring samples were taken in Boring 1 at depth intervals of 13, 17, 20, 23.5 and 27 feet. These were tested for soil density. Density test results are tabulated in a following section of this transmittal. Laboratory Maximum Density Maximum density determinations were made on each soil type observed in the field. Maximum density test procedures were conducted in accordance with ASTM D 1557 -78 Test Method A. Results are tabulated in a following section and utilized in calculating percent compaction of on -site soils. 4 Consolidation Tests One - dimensional consolidation tests were performed on 2 3/8 inch ring samples from depths of 13, 17, 20, 23 1/2, and 27 feet. Soil samples were tested under a vertical load simulating the in -situ overburden pressure. Water was then added in order to observe its effect on the resulting settlement. Results of consolidation testing are shown in Plate 23. Moisture Determination Soil samples were retained from Borings 1, 2, and 3 at '® frequent depth intervals as indicated on the boring logs. The samples were tested in the lab for moisture content. Results are tabulated in the laboratory test data herein and depicted on the attached Plate 22. Moisture contents are compared with optimum moisture contents which were determined from maximum density testing. Standard Penetration Tests Standard penetration tests of on -site soils were conducted within the test borings at frequent depth intervals as indicated on the boring logs. The tests were conducted in accordance with ASTM D 1586. Resulting blow counts for 12 -inch penetration of spoon sampler are tabulated on the boring logs and in the laboratory test summary section, and are depicted on the -~ attached Plate 21. 5 SITE CONDITIONS General Description Encinitas Villas is a condominium project located east of Interstate Highway 5 along the north side of Encinitas Boulevard. Pertinent site features are depicted on Plate 1. The site consists of a nearly level graded area which supports three large, two -story buildings. Each building includes five or six ground floor dwelling units with similar dwellings above. Construction is wood frame and stucco, supported on continuous foundations with lower slab - on -grade floors. The north sides of the buildings have paved parking and carport structures. The south side, adjacent to Encinitas Boulevard, is occupied by continuous yard areas with a well developed lawn. -- Site drainage is moderately -well developed. Paved parking areas along the north side are well- drained to adjacent streets. Rear areas generally drain westward and away from buildings in a positive manner. We understand from the homeowner's representative that regrading of rear yard areas was completed in the mid- 1980's in an attempt to promote improved drainage. Pre - grading conditions are unknown. Much of on -site roof drainage flows onto rear yard areas at down- -- drain outlets shown on Plate 1. Local ponding areas adjacent to building foundations pond surface waters approximately as shown. 6 Distress Dwelling units at the subject property are affected by moderate to locally high levels of distress, concentrated in the central areas of the project. The affected areas include all of the units in the 800 Building and the adjacent end units in Buildings 760 and 820. The most notable features are depicted on Plate 1. The distressed portion of the buildings is prominent and limited to the rear or south half of individual dwelling units. The most notable features include a perceptible downward deflection of lower floor surfaces with associated floor cracks. The floor .._ cracks project to large foundation cracks at the exposed end units LL of Buildings 800 and 820. Hairline stucco cracks affect the south exterior walls of the buildings. Inside, hairline cracks affect -_ wall surfaces particularly at corners along the south walls. The most prominent floor and foundation cracks are depicted on Plate 1. Floor cracks noted within individual units are shown on - the Manometer Survey Sheets, Plates 5 - 12. Photographs of many of the noted features are attached as Plates 24 - 27. 7 BACKGROUND The existing building site at the property was created in the late 1970's by filling into a natural canyon adjacent to Encinitas Boulevard. Construction of the existing buildings presumably took place soon after grading. At about the same time (prior to mid- 1979), a large diameter storm drain pipe was constructed within the fill along the southern property boundary. No construction details or history was available for our review. The pipe traverses the site very near the foundation line of the 800 Building. According to individual property owners within the project, W distressed features at the site were initially noted in the early 1980's. In March of 1984, a geotechnical study of the problem conducted by Benton Engineering, Inc. (see Reference 4) found loose soil conditions beneath the site and concluded that because of the granular nature of the soils, only 1/2 to 3/4 inches of additional settlement is likely to occur in the tested area near Unit 105 (Building 800). A later preliminary study (November, 1988) conducted by Impact General, Inc. (see Reference 5), noted distressed features only in Building 800 and concluded that the cause(s) could be due to poorly compacted soils, expansion, inadequate drainage or ground shaking during earthquakes. The consultant recommended a more detailed study. 8 FINDINGS Site Development Topographic maps of the project area prepared in 1960 depict a narrower Encinitas Boulevard and an adjacent natural canyon in the area of the study site. A copy of the early map is attached with this report as Plate 2. The project site was created in 1978 by filling into the canyon in order to create the existing building surface. Grading records for the work are unavailable for our review. However, a tentative tract map (No. 9317), on file with the County, references a soils report for the work prepared by w _ Rancho Santa Fe Engineering Co. (dated March 3, 1978). The soils report was not found in County records. The Existing Conditions Map, enclosed as Plate 3 indicates that the maximum fill depth is nearly 20 feet beneath the site parking lot areas. A lesser depth of approximately 15 feet is indicated beneath rear areas of the project. Storm Drain Subsequent work in the area of the project appears to include the installation of a large storm drain pipe along the southern property boundary. An easement area for the pipe was apparently recorded in 1969 prior to rough grading of the project site. However, the actual pipe construction probably took place at a later time. The precise construction sequence is not known to us. 9 As -Built plans for road improvement work along Encinitas Boulevard conducted in early 1979 depict the pipe along the southern property boundary of the study site. A reproduction of the As- Built Map is included as Plate 13. The pipe traverses the area in an east -west direction approximately as shown on Plates 1 and 13. The pipe location relative to the existing buildings (see Plate 1) was determined by encountering the structure in test boring excavations. As shown, the pipe crosses the area very near the foundation line of the 800 Building and the end units of the 760 and 820 Buildings. The pipe is a large structure. Available data indicates that it is constructed of. reinforced concrete with a diameter of 54 inches. The pipe is buried beneath existing grades to a depth of approximately 11 to 16 feet. Bedding or backfill soils around the structure consist of locally derived sandy soils as described on the enclosed boring logs. The soils surrounding the pipe were - -- found in a uniformly loose condition. Foundations: Two test pits were excavated adjacent to the end walls of Buildings 800 and 820 (see Plate 1). The pits were logged by our project geologist and utilized chiefly to expose foundation conditions beneath the buildings. Logs of the test pits are enclosed herein as Plates 18 and 19. As shown, foundations for the buildings in the exposed areas extend to a depth of 22 to 32 inches below adjacent ground surface levels. 10 Soil Conditions Fill soils directly support site structures to an approximate depth of 15 - 20 feet beneath existing grades. The fills consist chiefly of sandy soils with minor silt and clay. Details of the fill soil types are given on boring and test pit logs enclosed as Plates 15 - 19. Observations of in -place fill and soil test data indicate that the fill is in a moderately dense condition overall. Relative compaction levels generally range near the 90 percent standard required by local grading codes. However, a prominent zone of very loose and poorly compacted fill was encountered in all test borings. The loose soil occurs at approximate depths of 8 to 15 feet and likely represents backfill soil placed atop the storm drain pipe during construction. .._ Alluvial soils were encountered beneath on -site fill deposits. These are natural sandy deposits which occupied the natural canyon prior to site development. A section of nearly 20 feet of alluvium is indicated beneath the fill section. The alluvium occurs in a moderately dense condition in upper exposures and grades increasingly dense with depth. Soil deposits at the site are non - expansive. Bedrock materials underlie on -site soil deposits at depths of 35 - 45 feet below existing surface levels. The bedrock consists chiefly of sandstone units which occur in a dense, friable condition. Surface exposures of the bedrock were noted in large road cuts along the south side of Encinitas Boulevard. 11 The indicated configuration of earth materials beneath the study property is depicted on cross - sections enclosed with this report as Plates 4 and 14. Details of the soil /rock types beneath the site are given on the enclosed boring logs and test pit logs. The earth deposits are additionally defined by the soil test data which is tabulated in the following tables. TABLE 1 _ SOIL DENSITY DATA Boring 1 -- Moisture Dry Maximum Test Content Density Density Percent Test Earth Depth - ( %) cf cf Compaction Method Material 3 ' 18.7 105.1 121.7 86% SC Fill 6' 11 .9 113.1 121.1 93% SC Fill 9 ' 14.8 100.6 120.8 83% SC Fill 13' 9.8 110.0 125.0 88% R Fill 13' 8.9 108.1 125.0 87% R Fill 17' 13.0 113.0 125.0 90% R Fill 20' 15.0 108.0 120.8 89% R Alluvium 20' 15.0 113.5 125.0 91% R Alluvium 23.5' 6.3 104.0 113.5 92% R Alluvium 23.5' 13.6 112.7 120.8 93% R Alluvium - 27' 16.8 110.3 125.0 88% R Alluvium 27' 10.3 111.8 125.0 89% R Alluvium Boring 2 3 ' 14.3 110.6 121.7 91% SC Fill 6 ' 13.3 112.6 121.5 93% SC Fill 9 ' 14.7 97.2 120.8 81% DC Fill Note: SC: 6 -inch diameter sand cone. R 2 1/2 -inch diameter metal rings. DC: Large diameter drive cylinder. 12 TABLE 2 _ STANDARD PENETRATION /MOISTURE DATA Boring 1 Test De th SPT �_ Moisture ---_ � Blows /ft. Earth Material 5' 11.1 10' 13.9 24 Fill 15' 11.1 4 Fill 20' 12.9 10 Fill 25' 17.7 14 Alluvium 30' 16.7 17 Alluvium Alluvium 35' 17.9 47 Bedrock Boring 2 10' 13.0 15' 7.9 5 Fill 20 ' 12.5 11 Fill 25' 16.1 12 Alluvium 30' 11.0 12 Alluvium 35' 10.8 25 Alluvium 40' 14.8 30 A Alluvium Boring 3 5' _ 10' 16.0 17 Fill 15' 12.2 6 Fill 20' 12.7 11 Fill 2 25' 12.5 Alluvium - 30' 9.0 12 Alluvium 35' 8.9 25 Alluvium 40' 15.5 38 Alluvium Alluvium TABLE 3 _ MAXIMUM DENSITY /OPTIMUM MOISTURE DATA (ASTM 1557) Sample Soil Type Optimum Moisture Maximum Density B -1 @ 3' Silty Sand 10.5 B -1 @ 6' Clayey Sand 121.7 B -1 @ 9' 10.5 121.1 Silty Sand 10.9 120.8 B -1 @ 13' Coarse Sand with Silt 9.0 B -1 @ 23.5' Sand 125.0 B -1 @ 30' Silty M -C Sand 12.5 113.5 8.4 127.2 B -2 @ 6' Clayey Sand 10.5 121.5 13 The above soil test data is plotted on graphs, Plates 20 - 23. Plates 20 and 21 depict soil densities with depth. As shown, moderate density (compaction) levels are generally indicated which grade to increasing density with the deeper alluvial soils. An anomalous loose zone is indicated in all of the borings at _ approximate depths of 8 - 15 feet. Plates 22 and 23 depict moisture conditions within the underlying soils and the effects of added water. As shown (Plate 22), much of the on -site soils are presently at near - optimum moisture levels. Consolidation test results plotted on Plate 23 indicate a Potential within the underlying soils for added settlement with the introduction of increasing moisture. CONCLUSIONS /DISCUSSION Based upon the foregoing investigation, individual dwelling units at the Encinitas Villas project are affected by significant levels of distress. The most notable features include broken foundations -- and downward deflected and cracked floor surfaces. The distress is confined to the rear (south) half of dwelling units within the 800 Building and the adjacent end units of Buildings 760 and 820 (Plate 1). The property is underlain by a thick section of fill /alluvial soils which generally occur in a moderately compact condition overall. A local zone of very loose fill was encountered at depths of 8 - 15 feet adjacent to the rear foundation wall of the distress affected units. The loose fill represents backfill soils 14 which were placed over a large diameter storm drain pipe which traverses the area along the rear property boundary (Plates 1 and 13) . Noted site distress is chiefly the result of soil consolidation and local settlement in the vicinity of the storm drain pipe. This conclusion is supported by the following: 1. Patterns of site distress, including broken north -south foundations and downward deflected and cracked rear -floor surfaces, are consistent with local settlement of rear pad areas of the affected buildings. 2. Very loose soils associated with the storm drain pipe were encountered by our project geologist during down -hole logging of test borings B -1 and B -2. Loose soil conditions within the pipe zone were confirmed by laboratory test results and standard penetration resistance data (see enclosed tables). Similar loose soils have been reported earlier by Benton Engineering, Inc. (see Reference 4, Page 2). 3. Distressed areas at the project are confined to all of the units in the 800 Building and the adjacent end units of Buildings 760 and 820. As shown on Plates 1 and 13, these areas are very near the alignment of the storm drain structure and associated loose soil deposits. The indicated relationship of the pipe to the adjacent buildings is depicted on Cross - Section B -B' enclosed as Plate 14. 15 The precise potential for future settlement at the site, which will advance the noted distress, is difficult to determine. On- site soils are sandy materials which occur in a moderately compact to locally loose (pipe backfill) condition. Further consolidation and pad settlement will depend chiefly upon the availability of water to underlying soils. As shown on the enclosed Plate 22, much of the underlying soil section, particularly soils in the vicinity of test borings 2 and 3 0 , presently contain near - optimum levels of moisture. These soils therefore, have a significant Potential for the absorption of added moisture and resulting soil settlement. REPAIR ALTERNATIVES The following repair options are available for your consideration. The choice of the option depends on economic considerations and the degree of assurance required for minimizing the potential for future settlement. These repair techniques would require significant monitoring and control during construction. Option 1: Compaction grouting of the southern half of the structure and extending only to a distance of five feet outside the edge of the building. This procedure is feasible. However, there is a remote Possibility that it may affect the existing drain pipe. Compaction grouting is very effective when the soil mass is confined. For example, at this site compaction grouting will be 16 effective below a 10 -foot depth. It may be difficult to densify the top 10 feet of soil by compaction grouting because of the lack of adequate confining stresses. Therefore, the top 8 to 10 feet Of soil may require additional treatment such as lens grouting. The need for any lens grouting may be established, after _ compaction grouting is performed, by sawcutting a portion of the slab in one of the units and excavating a test pit for evaluating the soil conditions. If the soil indicates that its density has increased substantially, the lens grouting requirement and the cost of lens grouting could be eliminated. On the other hand, if it is determined that the compaction grouting did not materially change the percent compaction of near surface soils, the requirement of lens grouting may be added. Effective lens grouting can be accomplished by spacing the grout holes at 5 -foot intervals in the southern half of the residence. We estimate that for compaction grouting, the borings will be spaced in a grid pattern, the initial spacing of borings for compaction grouting is approximately 10 feet and closer spacing may be needed after monitoring the grout intake. However, we do Y not expect the spacing to be less than seven feet apart. For lens grouting the spacing would be approximately five feet. The grouting procedure also permits relevelling of the slab by mudjacking technique. However, portion of the slab will have to be removed and reconstructed in each unit to minimize the effects of differential movement which has already occurred. 17 Additional distress in walls and ceilings may occur during this process of compaction grouting. Further, since only part of the - floor area still remains on fill, there may be additional distress caused because of the difference in the stiffnesses of treated and un- treated sections of foundation -soil system. These anticipated distresses are expected to be of minor consequence and may be taken care of in a scheduled maintenance program. Option 2: The structure may be supported on caissons and grade beams. The spacing for the caissons will be approximately between 8 and 10 feet. The caissons should extend at least five feet into the formation sandstone. Actual depths are estimated to vary between 40 and 45 feet. The allowable bearing pressure will be approximately 8000 pounds per square foot (psf) on the sandstone which should be confirmed by testing of core samples from that depth during the construction phase. The caissons will consist of 2 -foot diameter concrete piers reinforced adequately. The advantage of caisson over other types of deep foundations is that the base of each caisson may be visually inspected by an engineering geologist in order to ensure adequate bearing materials. Since only part of the structure will be supported on caissons, minor distresses are likely to develop at the juncture between resupported areas and the existing foundations. As indicated earlier, such distresses are likely to be minimal. Relevelling of 18 the southern foundations can be performed during the underpinning process. One could also consider separating the slab from the foundation and constructing a floating slab for part of the flooring. A structural engineer's inspection and consultation will be required before the details of these repairs and construction procedures could be developed. Details of the required grade beam can be determined after an evaluation of the existing footing for steel reinforcements. Although unlikely, if the present footing consists of adequate reinforcements it may perform adequately as a grade beam. On the other hand, if the reinforcements in the footings are not adequate then new grade beams will have to be constructed under the existing footings. The details of grade beam reinforcements, caisson reinforcements and corbel requirements connecting the caissons and grade beams should be developed at a later stage in consultation with a structural engineer. O tion 3• Other types of piles can also be considered. Twelve inch diameter concrete filled pipe piles with reinforcement within the concrete, and with spacing of about four to five feet center to center, will adequately support the structure. However, the details of reinforcements and corbels will have to be developed in consultation with a structural engineer. The need for grade beams beneath the resupported wall remains similar to the caisson structures recommended above. 19 Other Recommendations In view of the granular nature of the site soils, we do not anticipate the need for a french drain system. However, there are areas adjacent to the structure with a potential for ponding. Minimal site grading will be required to eliminate ponding potential at the site. This opportunity to be of continued service is sincerely appreciated. If there are any questions, please do not hesitate _ to contact the undersigned. Sincerely yours, - Dr. Balakrishna Rao,. P.E. Dennis Middleton, CEG 980 Principal Engineer Principal Geologist For Middleton -Rao, Inc. BR/ DM /vc Q �pFESS/pH q � �KitISH�y y 2 W # 000709 W EXP l J'� FOF C AI 20 LIST OF ENCLOSURES SITE PLAN PLATE 1 PRE - GRADING CONDITIONS PLATE 2 EXISTING CONDITIONS PLATE 3 CROSS - SECTION A -A' PLATE 4 MANOMETER SURVEYS PLATES 5 - 12 AS -BUILT MAP PLATE 13 CROSS- SECTION B -B' PLATE 14 BORING LOGS PLATES 15 - 17 TEST PIT LOGS PLATES 18 - 19 PERCENT COMPACTION VS. DEPTH PLATE 20 BLOWCOUNT VS. DEPTH PLATE 21 MOISTURE CONTENT VS. DEPTH PLATE 22 EFFECT OF SATURATION ON DISPLACEMENT PLATE 23 PHOTOGRAPHS PLATES 24 - 27 o ti r ZY Q I 3 �, m J Q b Q \Nl - a W > o � � J _ W CL F mmm = mmmmm 8 p av aas) au// uo�joaS ssoao ' � 8 � � w • N `N I z u o Q Q O W ,M _o Ct y a O � Q m Q QQ J U J / CO N � 1 ( O O •ri N a-+ o N T1 U O •a 44 O O L1. 1 c0 d0 C C E F+ C .14 U U (� F+ Fr 4J C Cd O •o N �4 $ to E > i+ CD C N C F+ 'o U m O N "•1 O 4a CS • i ' • I • •..' ' O a.) O W 't7 0 C3 3 V ca O 4� 0 .,-1 O N a c� U +J N •H N K GO b0 K Id N t4 •.1 Cd co 41 O N Cd cti "o Q • 1 C "+ '0 6 4-1 0 U F+ H O N 0 es a-) to C • 4- u "o • 4a ^o N N O N CJ O C O O _ •'•1 CJ N Fr iU •.� 4J •-•r %0 4J O O +j N cd rs 'o O > .� C3 3. 4a 4a 4� U C .i O N N b �•J O O O O as 4a U it � • 4 41 CS C '' C C C C S•. O C 3 •14 •4 •1 K •� ai a x o t +J aJ O 4-1 o Ld J 1 � m _J --------- -- PRE-GRADING CONDITIONS 3//. PLATE 2 ®258 OR TREE , ( 313. I .1 308.0 - ��_� , v 239.0 13 - 10� �" I I I T. 13 S: �. f OI \ 228.E 5 X R C H o C; r B I.EVARD _ 4 ENCINI ?A � 22 5 W + I E5 +, 275 6 R U S A iw ir / X 2o2.0 ;', I CU ETI VATE D J !TREES 31(.0 1686E 1687E SCALE. 1:2400 4 � ,lea s � � i s# EXISTING CONDITIONS PLATE 3 k Note: Map is reproduced from San Diego County Topographic y r p. Map, Sheet No. 322 -1683. �3 Scale: 1" =200' •� ,� � t F � � � � F � :.r q g t FipgP a ` x'r;' � � "� as '� '�` � :n..,�;,,,,,,, is � ?� • "u." • t { R a O lffz Project Site i � .f3 p �.�s. ��.3. a �`a, p'` fte&' �` F� "a a.. •,: +' i � ar? 760 _ 8 A. ,+^'�`+,'°a �a •.; ''mow �w a � � .., •Q Ea.� k sv 1� I i Il a T ggggg rF � v E d. x 1687E _ o d y V1 0 0 0 O 0 u) N N O f y \ I L � N m • � W OO y _\ v _ Q m J I O w n. _ , cr- I� o .. Ltj -- V w w _j Q ,J .) J Q (� J LL J U v! � I p � n .y J Q N N (MOTO PLAN SCALE: 1 inch= 10feet Contours represent tenths of one inch %8 -Y4 s sa z� L U a-+ Y ENCINITAS VILLAS /800/101 NORTH vw� = Approximate location of crack Crack width indicated PLATE N0. 5 Consulting Engineers and Geologists Date Of survey 2-21-89 3 - DIMENSIONAL REPRESENTATION OF FLOOR SLAB NORTH ENCINITAS VILLAS /800/101 Approximate location of crack. No Scale Date of Survey 2-21-89 Consulting Engineers and Geologists PLATE 5 q PLAN SCALE: 1 inch = IOfeet Contours represent tenths of one inch b " 0 h A bat g Q c O X ENCINITAS VILLAS /800/102 v NORTH Approximate location of crack Width of crack indicated IL�IwOC�C��C�C OG1L ° �CS�O Doc. PLATE NO. 6 __ Consulting Engineers and Geologists Date Of survey 1-21-89 3 - DIMENSIONAL REPRESENTATION OF _ FLOOR SLAB NORTH ENCINITAS VILLAS /800/102 4 vyw = Approximate location of crack No Scale Date of Survey 2 -21 -89 Consulting Engineers and Geologists PLATE 60 µ PLAN SCALE. 1 inch = 70feet Contours represent tenths of one inch J J ha ..J 5 at8h 0 .J W L U be J ENCINITAS VILLAS /800/103 _J NORTH WW = Approximate location of crack Width of crack indicated. ��10vv��CS� !nt ° 11� 5n1 Op �C�1Q0 PLATE NO. 7 Consulting Engineers and Geologists Date of survey -21 -21-89 3 - DIMENSIONAL REPRESENTATION _ OF FLOOR SLAB NORTH ENCINITAS VILLAS /800/103 ^A4A= Approximate location of crack No Scale lulu �C�C��C�C�OCr�I � 1C�C�10 OG�1Go o Date of Survey 2 -21 -89 Consulting Engineers and Geologists PLATE 7 a l PLAN SCALE: 1 inch= 10feet Contours represent tenths of one inch l l I 32 1 ,6 1_ 0 b v x ENCINITAS VILLAS/800/104 1 NORTH = Approximate location of crack L1UL1��0��50 tnL ° 5n1 � D�Qo PLATE NO. 8 L Consulting Engineers and Geologists Dote Of survey 2-21-89 3 - DIMENSIONAL REPRESENTATION OF FLOOR SLAB NORTH ENCINITAS VILLAS /800/104 vwv = Approximate location of crack No Scale U1%Ll�vv0��0� ° � SnLOp ��Qo p 2 -21 -89 Da te of Survey Consulting Engineers and Geologists PLATE 8 0 PLAN SCALE. 1 inch= 10feet Contours -represent tenths of one inch rg y 8 23 8 7 3t L bath O 8 x 1 ENCINITAS VILLAS /800/105 l .1 NORTH Ivw%^ = Approximate location of crack I Width of crack indicated 1 PLATE NO. 9 Consulting Engineers and Geologists Date Of survey 2-21- 3 - DIMENSIONAL REPRESENTATION OF FLOOR SLAB 1 1 _1 1 1 1 NORTH ENCINITAS VILLAS /800/105 -� vwv� = Approximate location of crack 1. No Scale 1 0 01 @& Date of Survey -21 -89 1 Consulting Engineers and Geologists y PLATE 90 PLAN SCALE.' 1 inch= 70feet Contours represent tenths of one inch O y8 4„ bath 8 O ENCINITAS VILLAS /820/101 NORTH Location of crack, dashed is approximated. Width of crack indicated PLATE NO. 10 D Consulting Engineers and Geologists Date Of survey 2-21-89 3 - DIMENSIONAL REPRESENTATION OF FLOOR SLAB NORTH ENCINITAS VILLAS /820/101 AVvvv= Approximate location of crack -1 No Scale 1 Uuu�C�C��C��OC�1 ° �pQp �GL1C�o Date of 2 -21 -89 1 Survey consulting Engineers and Geologists PLATE 10 a PLAN SCALE l inch = lofeet Contours - represent tenths of one inch _I J its 0 u bath c Y bed ENCINITAS VILLAS /820/102 NORTH ��+ = Approximate location of crack PLATE NO. 11 Consulting Engineers and Geologists Date of survey 2 3 - DIMENSIONAL REPRESENTATION OF FLOOR SLAB NORTH ENCINITAS VILLAS /820/102 _ !Approximate location of crack No Scale U 20 ddu@Roomoaa, DWQ . Date of Survey 2 - 21- 89 Consulting Engineers and Geologists PLATE t 1 a PLAN SCALE' 1 inch= 10feet Contours represent tenths of one inch l ed 9 �l. / b 8 c v u Y 1. ENCINITAS VILLAS /760/106 ' I NORTH PLATE NO. 12 Consulting Engineers and Geologists Date Of SUr 2 �'` 1- 89 vey 3 - DIMENSIONAL REPRESENTATION OF FLOOR SLAB ?J NORTH ENCINITAS VILLAS /760/106 No Scale .J o Date of Survey 2 -21 -89 Consulting Engineers and Geologists PLATE 120 3HONd o,/ 6uinoui6u/ vJ v /uoy vy�av'y : 3wym S,833H utihjF :e Q o ?�=h uq x Ili 11, J I t Zl uiv lJ iYJ✓ f1G' � r ,n J r >. ►' `q z �W u op�Wti C4^��i i JJ CC > v W Q > �, IFYOd zs O� \\ EL V� �h vmi2i~a24 3 O Ww I 14 ICJ Arc o '= o I v \ � v `\ h p V � w . H h a W W .. ° Va i- �'�, s ••i�i� `^'•� rte, `� \ 1 z Q li y y > b i6 oc tea b' 1� Q I frJ txf gar n of 'o j 9 F 1 a ( D I V � . is i 4 � o M A v h J •.1 V 1 tic) CO Via: I v S I .Nm 11,1A WjV � (vf s6�/ 1 � /� fprary /l+c►y /JK : '�� `s Of /V 4 iv %� q - - w.6 V IV cc _ I � W � O w 7 I I _ v.� I a I > L ' I � o W 'l I u 4 ° 0 d O O N r 0 H — O c � • a ' ° a Gil m [2D Zj LL � o 0 Ir I J ,Q Z or h J i W J CO L 4 __ Q '° m N W o CS a � Q z _o Q U � O _ Q O V ,j 0 OD 1 m O O O N M �3or�o�� doh B -1 F Depth Sample Standard Description Pen. Data 6" 6 FILL Sand, silty and clayey, fine to medium, dark brown -- V (chocolate) 5 colored to brown color, very moist to wet, in upper three feet, moderately moist below. 5' V j 12,12,12 from 8 soil is very loose. -10 , from 12 - 15 encountered large concrete pipe at 10' north side of hole trending approximately N681t!. 2'2,2 Soil surrounding pipe is very loose. O1 15 from 18' 15 ' soil grades to firm. Slight organic O , odor. 514,6 oo ALLUVIUM 20 20 Sand, silty to slightly clayey. Fine to medium 5,6,8 grain. Medium brown color. A!icaceous. Slightly porous. Traces of organics at upper contact. - O , Moist, moderately firm. 25 25, _ from 23 soil includes layers of "clean ", tan 7 colored medium grain sand. a from 28 color of sand is uniformly dark brown. 30 ' Locally wet. 30` 7,8,10 FORMATIONAL ROCK v 35 Sandstone. Tan color. Medium grain. Friable. 35` End Boring @ 36' 11,16,31 SAMPLE LEGEND _ 40 , Bulk sample Project Encinitas Villas O Ring sample m _ No. 21- 0389 -D1 Date 2/23/89 By D. M. V Sand cone density Drill sample method 3' diam. auizer, sand cone Plate 15 Welpa �a@ B -2 Depth Sample Standard (ff.) Description Pen. Data 6" 6 "6" FILL Sand, silty, clayey, fine- medium grain. Dark brown - (chocolate), very moist. Organics. Loose. Moist to very moist. 5 V I sandstone8fragments. I'.emains�moistlandcloose, small from 3 - 10', color is mottled light tan to dark O ' brown. Soil grades to very loose. -10 /0• @ 10', large auger refused by large diameter 2,2,3 - concrete pipe which trends roughly east -west through center of hole. Soil surrounding pipe is very loose. Change to G" diameter auger and continue. 15 15' @ 15 soil is locally saturated. Includes 4,5,6 deposits OF-clean, medium grain sand. 20 ' ALLUVIUM 20 7, 5,7 Sand, silty. Medium brown with layers of clean, tan colored sand. Moderately firm. 25 25, 8, 5,7 30 30 8,10,15 from 33 grades chiefly to clean, tan colored, medium grain sand. Becoming increasingly dense with depth. 35 35 End Boring at 41' 1301,11 SAMPLE - 40 , Bulk sample Project Encinitas Villas O Ring sample -_ No. 21- 0389 -D1 Date 2/24/89 B JN 0 Sand cone density Drill amp sle method 3' diam. auger Plate 16 WaT O , QO) doh B -3 F Dept h Sample Standard Description Pen. Data _ 6"' 6 "6" FILL Sand, silty. Fine to medium grain. Tan to - medium brown color. Loose. Locally wet to moist. 5 5' 3 -10 ' @ 10' dark brown sand predominates. Remains /0' locally wet, very loose. 1,2,4 ..._ 15 15 4,5,6 ALLUVIUM Sand. Medium grain, silty and clayey. Medium - 20 brown. Moist. Grading to less fines with depth. 20 ' 4A5 5 25 25' 6,5 from 29 soil is dominantly tan colored "clean" medium grain sand. Gradink more firm with depth. 30 30 10 35 @ 39 soil is mottled tan to gray. Friable. 35' May be weathered formational rock. 13,15110 SAMPLE 40 End Boring at 41' Bulk sample 40' Project Encinitas Villas 15 17 1 21 - 0 -D1 2/24 Q Ring sample No. /89 By DM Date �'' Sand cone density Drill sample method 6" auger. Standard Pen Plate 17 aoc� Depth Plate 18 (in.) Description Symbol Sample Remarks _ E7 Soil Line 5 0 .. Fill SAND, silty, fine to _ medium grained, light 10 ��.� greenish brown color, concrete p 2 -5% sandstone fragments C' , footing moderately loose to moder- ately firm, moist, organic 15 o v. 20 v O 4 o o P footing _ 30 35' d. Fill T.D. 36" i T'oundation Crack f? Y Project No. 21 038.E -D1 Date 3-7-89 By JV T- 2 E (in h Plate 19 Description Symbol Sample Remarks FILL SAND, clayey, fine 5 . L7 rained, tan, moist. p SAND, silty, u white color, f -m 10 a' grained, moist. f ` J p SAND, silty, f -m 15 d O grained, greenish brown, sandstone frag -ments (2-5%) , dense -- 20 Q . moist. tr • � — 25 CONCRETE FOOTING 30 11 inches thick T.D. 25 35 Project No. 21-0389-DI r Date 3-7- �N .� By " °"` °---_ /"+..: I►inn Fn�inssnra :Inrl (;n�Innis►s �ddIlQ�o� oM@@ 9 GEOTECHNICAL CONSULTANTS sa 0.00 COMPACTION VS. DEPTH —5.00 —10.00 i —15.00 w 0 —20.00 —25.00 —30.00 80.00 85.00 90.00 95.00 100.00 ss COMPACTION ❑ 8- 1,SAND CONE A 8- 1,RING O B- 2,SAND CONE & DRIVE _ =PROJECT ENCINITAS VILLAS PLATE 20 0 0 0 � o �ddIlQ�o� �3ao Emeo 9 GEOTECHNICAL CONSULTANTS —a.00 BLOWCOUNT VERSUS DEPTH —5.00 l —10.00 L -15.00 L = -20.00 a w L ° —25.00 —30.00 —35.00 —4 -0.00 0.00 5.00 10.00 15.00 20.00 25.00 30.00 35.00 40.00 BLOW COUNT (BLOWS /FT.) ❑ BORING B -1 A BORING B -2 *BORING B -3 PROJECT ENCINITAS VILLAS PLATE 2-I GEOTECHNICAL CONSULTANTS 1 0.00 MOISTURE CONTENT VERSUS DEPTH 1 1 —10.00 _1 ..1 � _ —20.00 IL W 0 .1 1 —30.00 J _1 —40.00 0.00 10.00 20.00 MOISTURE CONTENT, sa O BORING B -1 A BORING B -2 O BORING B -3 X OPTIMUM P VILLAS PLATE 22 O d y o p -- o °o O O o � • • C7 E3 0 c to i O • DO • • • • 'f� C 0- _ Z (�5� �O� W `) W W U rq a ,C O ^ w 1 N OO C - O D Z z O Z O O z p - W ir- Z O � i-- U. O U W LL. O • M (V W I— Q J _ a N O �t p O LO NIVNIS 1N3083d o r 4 i i i f. Large foundation crack west end of Building. Art , �a ....e •iY i � �'� , t IF I Y • YC.L M R S ` ' View looking cast at rear of Building 80�, Middleton - Rao, Inc PLATE 24 �U"WO�O��LJ�JU"U 1L�� r r MWlr.r. n Lar foundation crack inside closet at east end of k building. t t� \ cci I • 1. .. Foundation crack at west end of building. Middleton - Rao, Inc PLATE 25 f�H�TOG� A f�H f ' T k! z .. -7' _�� •p 1 t4 Yry X° Y I •PSliY'ilYY�i''�WW �. A y � ..nr y � �,� � f f�HOTOG�A�H f Z ...rv...+. r nw►w+roe'r � i:y,t 1 � - L_ ( ! J �� .. � 1 0l� Y ., a - -�� f ; � �� /►« f ..,.. sp � � � f .0 GEOTECHNICAL INVESTIGATION OF DISTRESS Encinitas Villas 760, 800, and 820 Encinitas Blvd. Encinitas, California :.M HETHERINGTON ENGINEERING, v I INC. GEOTECHNICAL INVESTIGATION OF DISTRESS Encinitas Villas 760, 800, and 820 Encinitas Blvd. Encinitas, California HETHERINGTON ENGINEERING, INC. GEOTECHNICAL INVESTIGATION OF DISTRESS Project No. 353.1 October 13, 1989 Page 2 �Y The soils were visually classified according to the Unified Soil Classification System. Classifications are shown on the attached Boring Logs, Figures 3 through 12. The following laboratory tests were performed: • Dry Density and Moisture Content (ASTM: D 2216) • Maximum Dry Density and Moisture Content (ASTM: D 1557A) • Particle -Size Analysis of Soils (ASTM: D 422) • Consolidation (ASTM: D 2435) The relative compaction and degree of saturation of each fill soil sample was also determined. Results of dry density and moisture content determinations are presented on the Boring Logs. Results of remaining laboratory " tests and the relative compaction and degree of saturation determinations are presented on Figures 13 through 17. SUBSURFACE CONDITIONS The subsurface conditions revealed by our borings were generally in w close agreement with those described in Reference 5. Generalized subsurface conditions are shown on the attached Cross - Section A- A'. The local zone" of very loose fill described in Reference 5 W appears to extend from 5 to 15 feet below the ground surface on the south side of the "distress affected units ". Our Boring No. 6 indicates that the fill soils on the north side of the units is generally medium dense to dense within this zone. LOCATION OF STORM DRAIN As part of our investigation, the storm drain which traverses the property was located by survey techniques. The survey work was performed by Precision Survey and Mapping and their Topographic Survey Map served as the basis for our Plot Plan, Figure 1 which indicates the storm drain location. HETHERINGTON ENGINEERING, INC. GEOTECHNICAL INVESTIGATION OF DISTRESS Project No. 353.1 October 13, 1989 Page 3 CONCLUSIONS AND RECOMMENDATIONS 1. The reported and observed distress to the affected units appears to be the result of settlement of very loose fill due to the introduction of water and resulting from a differential fill compaction condition beneath the structures. The extent of the very loose fill zone is not precisely known. 2. Settlement of alluvium underlying the structures is not likely a contributing factor as the alluvium appears to be relatively homogeneous and deepens contrary to the direction of floor slab downward deflecticn. 3. Based on the results of our consolidation testing and that included in Reference 5, it appears that future settlement of the very loose fill soils is likely upon the introduction of water. We estimate future differential settlement on the order of 1/2 to 1 -inch. 4. To minimize the potential for future settlement of the very loose fill soils we recommended in -place densification utilizing compaction grouting techniques. Additional geotechnical investigative work would be necessary to determine the limits of grouting and provide grouting specifications. This opportunity to be of service is appreciated. If you have any questions, please contact our office. Sincerely, Y HETHERIN TO ENG N NG, INC. MAC N ON C' it n er 488 G ote ical En ineer 397 (bo expire 3/31/92) MDH /ss Attachments HETHERINGTON ENGINEERING, INC. 4 REFERENCES 1. "County of San Diego, Topographic Survey Map, Sheet 322 - 1683," dated July 1960. 2. "Plans for the Improvement of Encinitas Boulevard between Delphinium Street and Rosebay Drive," by R.L. Doane, dated June 1, 1978. 3. "County of San Diego Tract No. 3782, Map No. 9317," by Raymond Spencer, dated January 11, 1979. 4. "County of San Diego Topographic Survey Map, Sheet 322 - 1683," dated October 25, 1985. 5. "Geotechnical Investigation, Encinitas Villas, 760, 800, and 820 Encinitas Boulevard, Encinitas, California," by Middleton- Rao, Inc., dated March 21, 1989. 6. "Topographical Survey, Lot 1 of Map 9317 filed in the office of the County Recorder of San Diego County, August 2, 1979," by Precision Survey and Mapping, dated July 31, 1989. i HETHERINGTON ENGINEERING, INC. U N _Z z O W G ¢ z O t7 U — N W a J ► J r O O O O O O O O co 10 r N W sr 1p 0 1 OD ► 0 1 1 1 1 I I Q U Z Z W U W O O cc a 1 \ W Zc 1 W z o co wQ \ (� z 1 � a 4 � cn 1 N fr Z l \ Z U wo J 1 ; 0 Z � L a Q � v a ¢ z I Z = z ( �\ w H O w 0 1 � IL ` U 1 W Z 1 e ° m � z � a N a o m t z > 1 1 0 J � F ° D a a I ( oc F- J > ( O O Z J LL. N J z a ( :- w O ro _tom w O 1 J co m 1 ( a ' ' U a U W > 06 J a z O N c O Q 0 0 0 0 0 0 0 0 O T . N W W 1► m I 1 I 1 1 1 I 1 DR ILLING COMPANY: Geodr RIG: CME 550 DATE: 7/20/89 BORING DIAMETER: 8 DRIVE WEIGHT: 140# DRO 30" ELEVATION: ±2 00' W ° ~ O y LL ° z c z co V5 B NO. 1 Z CO W 0 � V U d O O }^. vi Z J W m o m o 1 O O U V) SOIL DESCRIPTION 0 FILL: Tan silty sand, moist to very moist, 28 109.2 E.3 SM medium dense 19 117.3 7.5 5 22 117.0 11.6 Medium brown silty sand, very moist, very loose 4 105.7 18:1 SM Concrete pipe @ 8�' 10 Total Depth 8'h' No Water 15 No Caving 20 25 30 BORING LOG HETHE ERGINEERINC Enci villas Condominium M GEOTECHNICAL CONSULTANTS PROJECT NO. 353.1 I FIGURE NO. 3 DRILLING COMPANY: Geodrill RIG CME 550 DATE: 7/20/89 BORING DIAMETER: 8 DRI WEIGHT: 140# DR OP: 30" ELEVATION: ± w a p of U < o z Cr Q^ BORING NO 2 y 2 _J 0i a ? O } w J ~ 1- ai Li o m o m o- O iD O SOIL DESCRIPTION u to .. 0 SM FILL: Tan silty sand, moist, loose to medium 36 106.3 4.) dense X32 119.4 7.3 I 5 14 109.1 10.7 X10 No rec very Medium brown silty sand, moist, very loose to 6 104.3 14.2 SM loose 10 8 107.4 9.9 7 96.6 11.11 15 Tan -brown silt sand, moist, loose ALLWIUM- Y SM 20 11 103.0 11. Total Depth 21' No Water No Caving 25 t 30 BORING LOG HET HERIN T'ON ENG[HEERINC I I Encinitas Villas Condominium GEOTECHNICAL CONSULTANTS PROJECT NO. 353.1 I FIGURE NO. 4 DRILLING COMPANY: Geodrill RIG: CME 550 DATE: 7/20/89 BORING DIAMETER: 8 91 DRIV WEIGHT: 140 DR OP: 30" ELEVATION: ±185' W _j n. O f- at vi U. 7 ° Z c z J 0i BORING NO. 3 2 0) W 3 _ f' FW- U U O O SOIL DESCRIPTION W m p m � � U vi.. 0 FILL: Tan silty sand, moist, very loose 6 No re overy Sbf ' Encountered water pipe @ 3'h' - boring abandoned 5 Total Depth 3h` 10 15 20 25 30 BORING LOG HETHERINGTON ENGINEERING Encinitas Villas Condominium GEOTECHNICAL CONSULTANTS PROJECT NO. 353.1 I FIGURE NO. 5 N DRILLING COMPANY: Geodr RIG: CME 550 DATE: 7/20/89 BORING DIAMETER: 8 DRIV WEIGHT: 140# DROP: 30" ELEVATION: ±200' H W W J G. 0 ~ LL 2< U- �' x ►- co BORING NO. 4 CO W z Z to W F U U .. W m p cc m 0 N v SOIL .DESCRIPTION 0 SM FILL: Tan silty sand, moist to very moist, very 10 107.4 18.0 loose to loose 11 110.2 14. 5 4 102.9 13.2 Dark brown mottled silty sand, moist, very loose 6 108.1 11.0 SM ALLUVIUM: Dark brown silty sand, moist, very 5 106.2 11.' SM loose to medium dense 10 15 10 104.6 11.6 20 22 120.7 10.4 BEDROCK: Tan sandstone, moist, very dense 25 Y50 -5" 100.0 8.9 30 BORING LOG HETHERINGTOk ENCINEERIRG Encinitas Villas Condominium GEOTECHNICAL CONSULTANTS PROJECT NO. 353.1 I FIGURE NO. 6 DRI LLING COMPANY: Geodril! RIG CME 550 DATE: 7/20/89 BORING DIAMETER: 8" DRIVE WEIGHT: 140# DROP: 30" ELEVATION: Uj W J O ~ W CL �.. C (0 � W = S�; BORING NO. 5 W U a O O > co vi o m p m o 2 v 0- SOIL DESCRIPTION 0 �SM FILL: Tan silty sand, moist, very loose to loose r 112.9 11.2 No rec very 5 — — - Med -ium brown silty sand, moist to very moist, 4 No recovery SM very loose to medium dense 6 103.3 19:9 10 `22 111.4 12.4 SM Tan silty sand, moist, medium dense ALLUVIUM: Tan silty sand with zones of dark brown 15 25 107.6 7.1 SM silty sand, moist, medium dense 20 @ 20' - becomes tan, medium to coarse slightly 22 108.9 14.3 gravelly sand, moist, medium dense SM 25 21 99.4 5.5 30 BORING LOG HETHERINGTON ENGINEERING Encinitas villas condominium GEOTECHNICAL CONSULTANTS PROJECT NO. 353.1 I FIGURE NO. 7 _ I DRILLING C OMPANY: Geodrill RIG CME 550 DATE: 7/20/89 BORING DIAMETER: 8 DRIVE WEIGHT: 140# DROP: 30" ELEVATION: ±200' LU Uj d ~ T ^ W O F- - to U w ? z 15 Vi BORING NO. 5 (Continued) > ^ O O O� W m p m o— i C 0 SOIL DESCRIPTION 30 18 117.0 14.0 ALLUVIUM: Medium brown silty sand, very moist, SM medium dense to dense 35 12 112.0 17.7 i t 40 19 105.6 22.3 45— 18 112.4 17. I 50 i 55 80 BORING LOG HETHERINGTON ENGINEERING Encinitas Villas Condominium GEOTECHNICAL CONSULTANTS PROJECT NO. 353.1 I FIGURE NO. 8 DRILLING COMPANY: Geodrill RIG: CME 550 DATE: 7/20/89 BORING DIAMETER: 8 DRIVE WEIGHT: 140# DROP: 301f ELEVATION: ±200' Uj W w d 0 W _j CL W j 5 ai BORING N O. 5 (Continued) W C3 W M m OJ m y v O m i SOIL DESCRIPTION p m � .. 60 ALLUVIUM: Medium brown silty sand, very moist, SM loose to medium dense BEDROCK: Tan -brown sandstone, moist, very dense '50 - 4q' 106.5 17.8 65 70 Total Depth 65' No Water No Caving 75 I 80 85 80 BORING LOG HETHERINGTO ENGI Encin villas Condominium GEOTECHNICAL CONSULTANTS PROJECT NO. 353.1 ( FIGURE NO. 9 DRILLING COMPANY: Datum Exploration RIG: Mobile B -61 DATE: 8/16/89 BORING DIAMETER: 8 DRIVE WEIGHT: 140# DROP: 36" ELEVATION: ± 200' .. LL M-C U_ z o 5 0 BORING NO. 6 f� V U a O O O O� W m o m o SOIL DESCRIPTION 0 SM FILL: Tan silty sand, moist, medium dense '' 42 116.3 10.5 5 55 116.8 9.4 SM Brown silty sand, moist, medium dense to dense 10 36 98.3 17.4 SC Brown slightly clayey sand, very moist, medium 15 dense 45 107.7 14.1 SM Greenish -brown silty sand, moist, medium dense : ALLUVIUM: Tan silty sand, moist, medium dense SM 20 21 100.1 6.6 Tan to brown silty sand, very moist, loose to SM medium dense 25 — 16 105.5 19.3 SM Tan silty sand, moist, medium dense @ 29' - some gray clayey sand lenses 30 BORING LOG HETKERINGTOR EIZGIREERIRG I Encinitas Villas Condominium GEOTECHNICAL CONSULTANTS PROJECT NO. 353.1 I FIGURE NO. 10 i I DRILLING COMPANY: Datum Exploration RIG: Mobile B -61 DATE: 8/16/89 BORING DIAMETER: 8 DRIVE WEIGHT: 140# DROP: 36" ELEVATION: ±200' W w a O a� BORING NO. ` W a O a) w < � .. 6 (Continued) U_ W = Z J (� 3 ., z J _ f-- o m p m o O G O U N SOIL DESCRIPTION v 30 27 111.8 17. 2 SM ALLUVIUM: Tan silty sand, moist, medium dense 4 @ 34' - becomes sandier, moist 35 33 103.3 13.5 @ 39' - becomes siltier sand 40 22 111.5 17.2 45 i x.33 104.3 19.4 I 50 @ 50' -52' becomes wet 31 102.4 22.7 55 •� 29 104.0 13.9 80 BORING LOG HETHERINGTON ENGINEERING I Encinitas Villas Condominium GEOTECHNICAL CONSULTANTS PROJECT NO. 353.1 I FIGURE NO. 11 DRILL C OMPANY: Datum Exploration RIG: Mobile B -61 DATE: 8/16/89 BORING DIAMETER: 8 DRIVE WEIGHT: 140# DROP: 36 11 ELEVATION: ±200' W J - a ~ O F 2^ 05 LL t O� 5 BORING NO . 6 (Continued) Z W m p m o O 00 SOIL DESCRIPTION I 60 26 No r-covery SM ALLUVIUM: Tan silty sand, moist, medium dense @ 58' - some coarse - grained red and gray -brown sands with small pebbles I 65 K'100/1 97.0 16.0 BEDROCK: Orange silty sandstone, moist, very dense M M 70 N Total Depth 70' No Water 75 No Caving 80 85 90 BORING LOG HETHERINGTO R ENGINEERINrA I Encinitas villas Condominium GEOTECHNICAL CONSULTANTS PROJECT NO. 353.1 I FIGURE NO. 12 i LABORATORY TEST RESULTS SUMMARY OF MOISTURE /DENSITY RELATIONSHIPS Field Field Optimum Maximum Degree 1 Test Moisture Dry Moisture Dry of Relative Location Content Density Content Density Saturation Compaction M (Pcf) (-%) (Pcf) M C O . - ) I B -1 @ 1' 6.3 109.2 10.0 124.5 31.3 88 I B -1 @ 3' 7.5 117.3 10.0 124.5 46.4 94 B -1 @ 5' 11.6 117.0 10.0 124.5 71.2 94 I B -1 @ 7' 18.1 105.7 10.5 122.0 82.3 86 B -2 @ 1' 4.0 106.3 10.0 124.5 18.5 85 I B -2 @ 3' 7.8 119.4 10.0 124.5 51.2 96 B -2 @ 5' 10.7 109.1 10.0 124.5 53.1 88 B -2 @ 9' 14.2 104.3 10.5 122.0 62.3 85 B -2 @ 11' 9.9 107.4 10.5 122.0 47.0 88 B -2 @ 15 11.4 96.6 10.5 122.0 41.4 78 B -2 @ 20' 11.2 103.0 10.5 122.0 47.6 79 B -4 @ 1' 18.0 107.4 10.0 124.5 85.5 86 B -4 @ 3' 14.7 110.2 10.0 124.5 75.1 88 B -4 @ 5' 13.2 102.9 10.0 124.5 55.9 83 B -4 @ 7' 11.0 108.1 10.5 122.0 53.2 88 B -4 @ 9 11.3 106.2 - - 52.0 - B -4 @ 15' 11.6 104.6 - - 51.3 - B -4 @ 20' 10.4 120.7 - - 70.9 - B -4 @ 25' 8.9 100.0 - - 35.1 - B -5 @ 1' 11.2 112.9 10.0 124.5 61.4 91 B -5 @ 7' 19.9 103.3 10.5 122.0 85.2 84 B -5 @ 10 12.4 111.4 10.5 122.0 65.3 91 Figure No. 13 Project No. 353.1 SUMMARY OF MOISTURE /DENSITY RELATIONSHIPS (Continued) Field Field Optimum Maximum Degree Test Moisture Dry Moisture Dry of Relative Location Content Density Content Density Saturation Compaction ( %) (Pcf) (' °) (pcf) B -5 @ 15' 7.1 107.6 10.0 124.5 33.9 - B -5 @ 20' 14.3 108.9 - - 70.6 - B -5 @ 25' 5.5 99.4 - - 21.4 - B -5 @ 30' 14.0 117.0 - - 85.9 - B -5 @ 35' 17.7 112.0 - - 94.8 B -5 @ 40' 22.9 105.6 - - 100.0 - B -5 @ 45' 17.1 112.4 - - 9'2.5 B -5 @ 65' 17.8 106.5 - - 82.6 - B -6 @ 4' 10.5 116.3 10.0 124.5 63.2 93 B -6 @ 81 9.4 116.8 10.5 122.0 57.4 95 B -6 @ 12' 17.4 98.3 10.5 122.0 65.8 80 B -6 @ 16' 14.1 107.7 10.5 122.0 67.5 88 B -6 @ 20' 6.6 100.1 - - 26.1 - - B -6 @ 25' 19.3 105.5 = _ 8 7 . 3 - B -6 @ 30' 18.8 111.8 100.0 B -6 @ 35' 13.5 103.3 - - 57.8 B -6 @ 40' 17.2 111.5 - - 90.9 B -6 @ 45' 19.4 104.3 85.1 - B -6 @ 50' 22.7 102.4 = _ 9 4 . 9 - B -6 @ 55' 13.9 104.0 60.5 B -6 @ 65' 16.0 97.0 - - 58.6 I Figure No. 14 Project No. 353.1 MAXIMUM DENSITY /OPTIMUM MOISTURE CONTENT (ASTM: D 1557A) Sample Maximum Dry Density Optimum Moisture Location Classification (pcf) Content ( %) B -1 @ 0 -5' Tan silty sand 124.5 10.0 B -5 @ 5 -7' Medium brown sand 122.0 10.5 CONSOLIDATION (ASTM: D 2435) Swell( +) or Sample Normal Stress at Consolidation( -) Location* Saturation (psf) When Saturated ` B -1 @ 0 -5' 575 -0.11 B -1 @ 0 -5' 1150 -0.20 B -1 @ 0 -5' 1725 -0.23 *Samples remolded to 105 pcf @ 9.70 Figure No. 15 Project No. 353.1 US STANDARD SIEVE SIZES 7 3 2 1 3: h Y. 4 8 10 16 20 30 40 50 100 200 1 100 00 90 90 80 80 I 70 70 i 60 60 Z 50 50 0 in ? N N a a 40 40 Z w Z U w cc U a 30 30 Cr a 20 20 r 10 10 r 0 0 100 50 10.0 5.0 1.0 0.5 0.1 0.05 0.01 0.005 0.001 GRAIN SIZE (MILLIMETERS) GRAVEL SAND OBBLES SILT and CLAY Coarse Fine Coarse Medium Fine SYMBOL SAMPLE LOCATION FIELD %PASSING %PASSING UNIFIED SOIL MOISTURE W NO. 200 SIEVE 2y CLASSIFICATION B -1 @ 0 -5' _ 20 8 SM GRADATION TEST RESULTS KE'THERINCTQR ENGINEERING E n ci nitas Villas condominium GEOTECHNICAL CONSULTANTS PROJECT NO. 353.1 I FIGURE NO. 16 US STANDARD SIEVE SIZES 100 7 3 2 1 v 1 4 4 8 10 16 20 30 40 50 100 200 100 90 80 � 80 70 i 70 60 60 Wei Z 50 I 'M N 50 Z Q Erim d y f— 40 a Q w 40 U Z w a 30 ¢ 30 a 20 1 20 10 10 it I 0 100 50 10.0 5 0 1.0 0.5 0.1 0.05 0.01 0.005 0.001 0 GRAIN SIZE WILLIMETERS) OBBLES GRAVEL SAND Coarse fine Coarse Med um SILT and CLAY Fine SYMBOL SAMPLE LOCATION FIELD % PASSING % PASSING UNIFIED SOIL MOISTURE W NO. 200 SIEVE 2v CLASSIFICATION ® B -5 @ 5 -7' — 21 10 SM GRADATION TEST RESULTS HETHERINGTON ENGWEERIKG Encinitas villas Condominium GEOTECHNICAL CONSULTANTS PROJECT NO. 353.1 , FIGURE NO. 17