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1995-4464 G Street Address g�(0 Category Serial # Name Description Plan ck. # Year recdescv AWMWAM ® OMAN AIsAIW A®AMAW0 AXW ®®®®®®® ®� `iiii` consulting engineers and geologists January 12, 1987 �,_ t_ Mr. Daniel H. Wiegand SF -661 P.O. Box 515 Olivenhain, CA 92024 Subject: GEOLOGIC AND SOILS ENGINEERING INVESTIGATION 25 + ACRE HILLSIDE PARCEL LONE JACK ROAD ENCINITAS, CALIFORNIA Dear Mr. Wiegand: In accordance with your request, this office has completed a geotechnical study of the subject property. The site entails nearly 25 acres of undeveloped hillside terrain west of Lone Jack Road, north of the intersection with Fortuna Ranch Road, as depicted on the Geologic Map enclosed herein as Plate 1. A topographic base map has been provided and is utilized herein for the presentation of geotechnical data generated during this investigation. The accompanying report summarizes the results of our field investigation, laboratory testing, and provides our engineering analysis, discussions, and conclusion(s). Seyed Shariat and Dennis Middleton were our engineer and geologist, respectively assigned to this project. This opportunity to be of service is sincerely appreciated. If there are any questions, please do not hesitate to contact the undersigned. Sincerely, Dr. Balakrishna Rao, P.E. Vice President (Engineering) for SANTA FE SOILS, INC. BR /vc 11080 Roselle Street, Suite A • San Diego, CA 92121.619- 455 -7760 z ' A � MR. DANIEL H. WIEGAND P.O. BOX 515 OLIVENHAIN, CA 92024 GEOLOGIC AND SOILS ENGINEERING INVESTIGATION 25 + ACRE HILLSIDE PARCEL LONE JACK ROAD ENCINITAS, CALIFORNIA Prepared by: SANTA FE SOILS, INC. 11080 ROSELLE STREET, SUITE A SAN DIEGO, CA 92121 SF -661 January 12, 1987 v SF -661 Page 1 SITE DESCRIPTION The subject property is dominated by nearly flat -lying terrain which characterizes the lower areas of the site adjacent to Lone Jack Road. Natural slopes ascend westward over 160 vertical feet onto the upper ridge terrain in the western portion. Slope gradients approach 2:1 (horizontal to vertical) at their steepest. Details of site topographic conditions are depicted on Plate 1. Lower areas of the property support a light cover of native grasses. Chaparral -type brush predominates in the upper slopes. Several small trees mark the course of a small stream which flows across the eastern margin along Lone Jack Road. Site drainage sheetflows over the slopes toward the lower stream. Local gullying and erosion was apparent within upper, off -site slopes which descend below the northern property boundary. PROPOSED DEVELOPMENT Details of the planned development are currently unavailable. However, we understand that the upper property (designated Parcel 1 on Plate 1) is planned to support a single - family residential structure in the near future. No significant grading is proposed. Lower areas (designated Parcels 2 -4) are presently considered for future single - family residential development. An improved entrance roadway is planned. A small bridge or other suitable structure is required to crass the creek and provide entrance onto the property from Lone Jack Road. Sr -661 Page 2 SITE INVESTIGATION Geotechnical conditions on the subject property were determined from field mapping of surface exposures, and the excavation of six, two foot diameter test borings. The borings were downhole logged by our project geologist, and representative samples of underlying earth deposits were retained for laboratory testing. Relatively undisturbed ring and bulk samples were taken as indicated on the enclosed Boring Logs, Plates 3 through 9. The samples were sealed in moisture resistant containers and transported to the laboratory where the following tests were performed. * Maximum Dry Density and Optimum Moisture Content per ASTM D 1557 * Sieve Analysis per ASTM D 422 * Swell Tests under 150 psf surcharge * Consolidation Tests * Direct Shear Tests * In -situ Density and Moisture Content * Liquid Limit, Plastic Limit and Plasticity Index Tests per ASTM D 4318 -83 * Expansion Index Tests per U.B.C. Standard Procedure 29 -2 Results of the sieve analysis tests and the consolidation tests are graphically presented on Plates 10 through 15. The remaining test results are tabulated on Tables 1 through 5 in the following section. SF -661 Page 3 FI NDINGS Earth Materials Hillside areas in the vicinity of the subject property are underlain by sedimentary formational rocks which are mantled by surficial soil deposits. Two major formational units occur at the site which exhibit different engineering properties and slope stability characteristics. Higher ridge terrain at the site is underlain by light - colored sandstone units which are massive and moderately well cemented. These rocks generally support steeper slopes and are mantled by surface soils which typically support chapparal -type vegetation. Slopes underlain by local sandstone units are characteristically stable. The rocks are generally low expansive. Overlying surface soils and weathered rock materials are moderately to highly expansive. Lower slopes at the property are directly underlain by siltstone /claystone units. These rocks are characterized by their distinctive color which ranges from gray to green, and the common development of a thick natural soil cover. These rocks typically underlie lower, more gentle hillside areas in the vicinity and usually support a light cover of native grass. Local siltstone /claystone rocks are further characterized by their frequent association with slope instability and highly expansive soil /rock units. Lowest areas of the subject property are directly underlain by natural alluvial soils. These chiefly include stiff sandy clay and more recent sandy soils within the creek bottom adjacent to Lone Jack Road. Volcanic bedrock units were encountered beneath the alluvial soils along the eastern margin of the property. These are hard, f T SF -661 Page 4 massive rocks which predominate in surface exposures throughout hillside areas to the east. The approximate surface distribution of major earth deposits on the subject property is depicted on Plate 1. The indicated subsurface conditions are shown on Cross- Section A -A' enclosed as Plate 2. Ground Groundwater seepage, apparently representing the watertable, was encountered at 9 feet and 3.7 feet below the ground surface at the lower elevations of the site in Borings 5 and 6, respectively. Groundwater levels are expected to fluctuate / locally with seasonal or othor changes. Laboratory Testing The following results have been developed from laboratory testing of earth deposits on the subject property: TABLE I Maximum Dry Density and Optimum Moisture Content (Laboratory Standard ASTM D- 1557 -78) Sample Max. Dry Optimum Lo cati on D ensity (p c£) Moisture Conte B -1 @ 9' 114.7 16.3 B - @ 31 -5' 120.5 12.8 B -3 @ 3' 112.0 15.7 B -4 @ 21 109.5 17.2 B -5 @ 4' 125.3 11.0 B -6 @ 4' 11-4.0 15.8 B -6 @ 10' 112.5 15.2 c SF -661 Page 5 TABLE II In -situ Dry Density and Moisture Content Sample In -situ Dry In -situ Moisture Location Density (pcf) Content ( %) B -1 @ 15' 115.8 12.7 B -2 @ 5' 105.8 15.7 B -2 @ 10' 124.6 12.5 B -2 @ 18 130.7 10.2 B -3 @ 3' 108.1 9.3 B -3 @ 46' 118.7 11.3 B -4 @ 2' 95.9 25.2 B -4 @ 20' 102.8 22.1 B -5 @ 4' 104.2 23.0 B -6 @ 4' 111.1 13.5 B -6 @ 6.5' 110.9 15.1 B -6 @ 10' 106.1 20.3 TABLE III Swell Test Results (150 psf surcharge) Sample Location Sample Condition Swell ( %) B -4 @ 2' In -situ 4.3 B -6 @ 4' 90 percent remolded 7.3 f i SF -661 Page 6 TABLE IV Expansion Index Test Results (U.B.C. 29 -2) Sample Remolded Moisture Saturated Moisture Expansion Location Content ($) Content M Index B -2 @ 3' -5' 12.0 30.8 81 B -3 @ 3' 11.8 29.0 81 B -4 @ 2' 14.2 39.2 122 B -5 @ 4' 10.2 21.9 39 B -6 @ 4' 13.6 31.0 89 TABLE V Liquid Limit, Plastic Limit, Plasticity Index Test Results (ASTM D 4318 -83) Sample Liquid Limit Plastic Limit Plasticity Location (o) (o) Index B -1 @ 9' 35 20 15 B -3 @ 3' 33 24 9 B -4 @ 2' 45 16 29 B -5 @ 4' 45 18 27 B -6 @ 4' 43 17 26 TABLE VI Direct Shear Test Results Sample Sample Angle of Internal Apparent Location Condition Friction Cohesion (psf) B -1 @ 5' Undisturbed 23 1200 B -2 @ 5' Undisturbed 29 880 B -3 @ 3' Undisturbed 34 580 r SF -661 Page 7 Slope Stability Upper slopes at the property do not evidence instability. Sandstone units beneath the site are massive, moderatply -well cemented units which typically perform well in slope conditions. Local surface erosion of the upper sandstone is a result of uncontrolled drainage runoff. In contrast, cl.aystone formational units at the property evidence slope instability. Near- surface exposures are deeply weathered to a weakened condition which extends to an indicated depth of approximately 13 feet below the surface. The affected rocks develop a "creep zone" which slowly moves downslope over the less weathered rocks below. Creep affected slopes at the property are indicated by non- uniform topography and unusually moist areas which support a lush cover of green grass and wild dill plants. The more prominent creep affected areas within on- site slopes are indicated on Plate 1. No indication of gross geologic instability was indicated within hillside areas of the subject property. Seismicity The site lies within a seismically active region. No unique seismic hazards are anticipated for this site; however, groundshaking will likely periodically occur as a result of earthquakes on local or distant active faults. No known active faults are mapped through the site on the County of San Diego Faults and Epicenters map. x SF -661 Page 8 CONCLUSIONS Development of the subject property for the residential purposes is feasible from a geologic and soils engineering viewpoint. Conclusions presented below are pertinent geotechnical points which are relevant to the development of Parcel 1, and which will assist in planning for the future development of Parcels 2 - 4. Parcel 1 1. Slope instability which would be likely to affect Parcel 1 is not indicated. Sandstone formational rocks which underlie the upper hillside are sufficiently dense and will adequately support residential structures. The rocks are considered to have a low potential for expansion in unweathered exposures. 2. Upper sandstone units at the site are sensitive to uncontrolled surface runoff. 3. Topsoils which mantle the upper terrain at the site are clayey soils which, in their present condition, are not suitable for the support of structures. They are considered detrimentally expansive, as are weathered sandstone materials just below the soil section. Parcels 2 - 4 1. Claystone formational rocks, which underlie slope areas of Parcels 2 - 4, are weak units which may perform poorly in graded and natural slopes. Special consideration should be given to grading in these materials. 2. Much of Parcels 2 - 4 are underlain by sandy to clayey alluvial soils which are in a loose to soft condition. These soils will require special treatment during development which can be determined upon review of specific development details and once site specific studies are made. 3. Earth deposits underlying much of Parcels 2 - 4 are expansive. a SF -661 Page 9 4. Groundwater was encountered in lower elevations of Parcels 2 - 4. RECOMM The following recommendations have resulted from the foregoing geotechnical study, and are intended to help result in a safe and stable development. Parcel 1 Grading On -site topsoils should be removed to the underlying formational rock in areas planned for development. Removal depths of 2 -5 feet from existing levels may be anticipated. Topsoils or other expansive materials should not be placed as fill within three feet of finished grade elevation. If expansive soils are placed within three feet of finished grade elevation, varying levels of distress to structures located on these soils may be anticipated. Fill soils should be brought to near or wet of optimum moisture levels and mechanically compacted in thin, horizontal lifts to a minimum 90 percent of - the laboratory maximum dry density as determined by ASTM D 1557. All grading should be done in accordance with the San Diego County grading ordinance. Significant fill or cut slopes are not anticipated on Parcel 1 at this time. Upon availability of the proposed grading plans, this office should be notified in order to evaluate the need to SF -661 Page 10 conduct a site specific investigation. Compressibility characteristics of the saturated soil materials may be determined considering the extent of proposed cutting and filling during the grading phase. Foundations Structural foundations resting on low - expansive formational rock or properly compacted fill should be at least 18 inches below the adjacent finished grade for one and two story structures. The structural foundations should also be reinforced with two No. 4 bars, one on the top and one in the bottom. The foundation may be designed for allowable soil bearing pressure of 1500 psf. The allowable soil bearing pressure may be increased by one third for wind and /or seismic loading. If detrimentally expansive soils (soils having EI greater than 20) are found to occur within three feet of finish pad grade, revised foundation recommendations will be necessary. Inspections Structural fill placed on Parcel 1 should be observed, tested and approved by the project soil engineer. Foundation excavations and all subgrade preparation should be approved by the project soil engineer prior to pouring concrete. Plan Review Finalized foundation and grading plans and other pertinent development details. should be reviewed and approved by this office. SF -661 Page 11 Parcels 2 - 4 Grading Upon availability of proposed grading plans, this office should be notified in order to conduct site specific investigations. For preliminary planning, the following recommendations apply. Graded fill slopes should be constructed at maximum 2:1 gradients. Cut: slopes should be planned for 2 :1 gradients, and supported by minimum equipment width stabilization fills. Specific details and recommendations can be provided once proposed grading plans are known. Areas planned for improvement within Parcels 2 - 4 should be regraded in order to densify the upper soils. Rem-oval should extend to a depth determined once grading details are available or as determined by the project soil engineer based upon grading inspections. This removal should apply to planned fill as well as cut areas. On -site soils are suitable for reuse as properly compacted fill; however, detrimentally expansive soils should not be utilized as fill within the upper three feet of finished grade elevation. If expansive soils are placed within three feet of finished grade elevation, varying levels of distress to structures located on these soils may be anticipated. Fill soils should be brought to near optimum or wet of Optimum moisture levels and mechanically compacted in thin, horizontal lifts to a minimum 90 percent of the laboratory maximum dry density as determined by ASTM D 1557. All grading SF -661 ILI ++a Page 12 I' should be done in accordance with the San Di ordinance or as recommended b Sa ego County grading .44 consideration of s Y nta Fe Soils, Inc., in s pecific adverse geotechnical conditions. Foundations: �., Specific recommendations can be provided at the buildin completion of rough grading when individual g plans are known. Inspections r Grading operations on Parcels 2 i - 4 should be inspected, tested and continuously This should include removed by the project soils removals 1 fill keying engineer. operations, and finished Y g and compaction grade work. Specific foundation and floor slab recomm be provided at the completion of rou g h endations can best. subgrade conditions are known, grading when actual Plan Review: Finalized development submitted to this office for l review prior Parcels 2 4 should be prior to grading. BR_ ID E/ROADWAY We understand that a small bridge structure near the east boundary to provide access may be planned private roadwa to the property along a currently unavailable. SF -661 Page 13 However, the following preliminary recommendations should be considered: 1. The bridge should be supported on deep foundations which penetrate surficial soils and are sufficiently founded into the underlying bedrock materials. Soils parameters associated in this regard will be provided once the location is finalized and plans are available. 2. During grading operations, the soils underlying the roadway should be specifically tested in order to determine the thickness of the pavement structural layers. Detailed recommendations for the roadway construction will be provided at that time. This o pportunity to be of service is sincerely appreciated. If there are any questions, please do not hesitate to contact this office. Sincerely, SANTA FE SOILS, INC. Richard K. leek Dennis Middleton CEG980 Senior Staff Geologist Chief Engineering Geologist Seyed Shariat Project Engineer RKF /DM /SS /vc M `M Sr -661 plate 1 see map case BORING LOG n; E o Description m O Ring Sample El Bag Sample NATURAL SOI Sandy clay, olive to brown color with abundant white gypsum deposits scattered throughout. Moist, soft to stiff. From 3', weathered claystone fragments are perceptable. 5 Color is locally maroon. FORMATIONAL RO CK: Claystone /siltstone, pale grey with rusty brown zones. Weathered to loose "popcorn" consistency. Moist. Rock is likely affected by downslope creep which extends to depth of 13 feet. 10 From 8', rock is moderately hard and locally blocky. Remains fractured, moderately tight. From 13 rock increasingly hard, moderately fractured and moderately blocky, no apparent structure. 15— O F 10 At 16 nearly horizontal structure on Z" thick gypsum bed. 20 At 23', approximate: attitude on thick gypsum seam: N65W /18NE. At 25', attitude on thin rust colored seam: N1.5W /22E. 5 At 29 Water seep from north side of hole seepage emminates from 3" fractured bed oriented: N65E/29S. Below rock is very tight. n� 5 END OF BORING AT 35' Projecr Lone Jack Property Job N o. SF -661 plate No. 3 Type of Rig Bucket Date 12 -22 -86 BY DM /RF Drill Hole No. 3-1 Hole Dia. 2 _ A w C w 11080 Roselle Street, Sulte A • San Dego, CA 92121 BORING LOG a� E o Description oi. in m O Ring Sample El Bag Sample NATURAL SOIL Sandy clay, brown, moist and soft to stiff. From 3 pale olive with white gypsum deposits through- out. Remains soft to stiff. 5 O 2 FORMATIONAL ROCK Claystope /siltstone. Pale gray with local maroon color patches. Fractured to popcorn texture, moderately hard, slightly moist. From 8', rock is increasingly tight, less fractured. 10 0 7 At 8.5', attitude on white gypsum seam: N70E /32N. At 15', attitude on gypsum seam: N60E /54N. From 15 rock is increasingly coarse, grading to fine grained sandstone /siltstone. Remains tight with irregular rusty brown zones. 15 0 10 Sandstone. Pale gray, medium to coarse grained with 20 clay matrix. Irregular zones of rusty brown color. Very tight, moderately well cemented, gradational contact above. 5 END OF BORING AT 25' 0 Projecr Lone Jack Property Job No. SF -661 plate No. 4 Type of Rig Bucket Date 12-22-86 BY DM /RF Grill Hole No. B 2 ' MA &TA Hole Oia. 1100 HOSei!e Sveer, scare A • San Diego. CA ,921X BORING LOG a� E ; Description o" <n Co O Ring Sample E] Bag Sample TOPSOIL Fine sandy clay, red brown, moist, soft. FORMATIONAL ROCK 0 3 Sandstone, off white color. Fine 'grained, massive, 5 friable to moderately well cemented, slightly :Hoist. 10 attitude on parallel dark mineral seams: N45W /9NE. 15 @ 18', attitude on n thick rust colored seam: N75W /11N. 20 At 21', apparent north dipping cross - bedding. From 21 sandstone is locally brown colored. 25— Siltstone, brown color, locally sandy to clayey. "Dirty' appearance. Very tight, moderately hard. Upper contact abrupt marked by 1" thick rust colored zone. Oriented: NIOE /5E. 0 Projecr Lone Jack Property Job No SF -661 plate N 5 Type or Rig Bucket Date 12 -22 -86 BY DM /RF Drill Hole No. B -3 Hole Dia. 2 TA A7 A _ i r �_ 1 MO Roselle Street, Suite A • San Diego, CA 92121 BORING LOG I 1 E Description m O Ring Sample Bag Sample @ 25', thick gypsum bed dips parallel to upper I contact. @ 26 1" thick gypsum bed with open structure oriented: N25E/26W. From 26 thin discontinuous cream colored seams, nearly 5 horizontal throughout. Randomly oriented gypsum seams throughout. At 30', 2' diameter well cemented limy nodule. Very hard. I Sandstone. Pale gray to off -white color. Fine to 40 medium grained. White gypsum streaks throughout. i Micaceous, massive, moderately well- cemented. From 35 sandstone, locally coarse and gravelly. I Claystone. Green color, rust -brown fractured surfaces. Locally sandy, white discontinuous gypsum streaks 5 throughout. Very tight, moderately hard, moist. 1 Upper contact is abrupt, nearly horizontal. 0 15(?) �so — END BORING AT 53' 5 I Proiecr Lone Jack Property Job No.SF - 661 Plate No. 6 Type of Rig Bucket Date 12 -22 -86 BY DM /RF I Drill Hole No.; B -3 ( cont ) Hole Dia. 21 MAA_A_ 11 00 Roselle Sbwt, Suite A • San Diego, CA 92121 BORING LOG n� E 3 Description o� N om O Ring Sample Bag Sample TOPSOIL 2 Red- brown, moist:, firm, sandy clay, roots and rootlets. 5 Sandy clay. Light brown with rust color (mottled). Moist, firm. 10 FORMATIONAL ROCK 'Sandstone, silty. Tan color. Grades to off - white. Massive. Friable. @ 7 black clay seam. Six inches thick. @ 16', one -half inch gypsum seam. Oriented: N20W /7E. 20 O 4 From 18 sandstone is increasingly tight and well- cemented. @ 34', yellow -brown sandstone. Locally hard. Six inches thick. 30 @ 36', dark mineral seam indicates cross - bedding. _ t aystone. Green color. Moderately fractured. Very ght, hard. Moist. Upper contact is nearly horizontal. 40 END BORING AT 46' 50 i, Proiecr Lone Jack Property Job No.S_r -6-6J Plate No. —7 Type of Rig Bucket Date 1223 By R Drill Hole No. B - 4 Hole Dia. 2� � 11080 Roselle Sheet, Suite A • San Diego, CA 92121 BORING LOG m a; e a Description o� m O Ring Sample El Bag Sample ALLUVIUM Fine silty sand. Iced- brow color. M oist, loo Sandy clay. Red- brown. Includes up to 40% volcanic rock fragments up to'5" in diameter. Moist, loose. 2 5 Sand, fine grain, silty. Brown color. Includes up to 30% cobbles. Moist, loose. Rock slows drilling progress. Unable to drive sample. 8' boulder (38" diameter) 10 From 9 small amount of water seeping into boring. BEDROCK Volcanic rock. Red color. Weathered in upper foot to soil with fractured rock consistency, very firm to hard below 11�'. 15 'ND BORING AT 13', BUCKET REFUSrD BY HARD ROCK IN BOTTOM 20 25 0 Project Lone Jack Property Job No. 1 ;F-666 Plate No. Type of Rig _ Bucket Date 12 - By DM Drill Hole No. B - 5 Hole Dia. 2 M A &T A 11090 Aoselle Slr f, Sidle A • San Diego. CA 92121 it t BORING LOG o� N m Description O Ring Sample 0 Bag Sample ALLU VIUM: S clay to clayey fine sand,. Brown color. Includes soft in hiterg2psum deposits throughout. Moist and stiff and firm below. 4 From 4 soil include patches of olive -brown soil. 5 Remains stiff to f.Lrm. O 4 — — Sandy 1 clay. Brawn, tan to ra 10 Includes small, white to g ray color (mottled). 3 gypsum deposits. Moist, stiff. Clayey sand. Medium to coarse locally gray. Moist, loose grain. Tan color, 15 a Sandy clay to clayey sand. Light brown to 60% volcanic pebbles to cobbles. Includes up slows.drillin 9 ,. Wet loose. Rock 17 heavy water seeps. Caving of lower -hole walls. 20 END BORING AT 17 , DEEPER BECAUSE OF LARGE B ROCK 10 AND G CAVING OI' WET SOIL 25 0 Pro)ecr Lone Jack Job No. S__ F-661 plate No. �_ Type or Rig Bucket -Auger Date 12 -23 -86 DM Drill Hole No. B -6 8Y Hole Dia. 21 MANTA 11090 RosolJe Svoe1, SLAo A • San O►ep p CA�92121 PERCENT RETAINED O N rn h io m Or e O y N O O O 4 N J v I lo 0 0 0 z � r O F O J H O z O H Q v to LL O N ° p ° a N J. Z O U O `� o H- w Q W 2 U O w (D ° �W N > Q w J J U) O J U o p to � _J z Q O z O cn ; p O N z N N _ 0 i F n d O N w (n N Z M a cr- W N O 1 i 0 O T T O 1 Vl m I _ N Z �\ r ° r Q � O l7 p W ~ ��N O V O M (n J O � � i0 m ' i � a U m m O p O O O O O O O p p N p 01 co ti W ul v M N PERCENT PASSING :LONE JACK PROPERTY t� S �PLAT E N o.F -66 GRAIN SIZE DISTRIBUTION CURVES PERCENT RETAINED O O N a0 N 0 00 0 p 0 LF N ! O O O 4 N u o c ac 0 0 z 0 F , o J N O z O O F- Q V N u. O to O p H N J. Z O v O C/) c o F- W Q W N N U v� oc N O C w W W W W J cn a J i p p v1 --� Q Q O z O V) p O ~ a N N W N N Z Cl) o O J D W N c 4 � 0 1 O � J I o T T O I W - - to A� O Q O cr = N W l7 O W M V O � z w o z O p u O p O O O O O p p O O N O_ co ti t0 to v M N PERCENT PASSING Proj ec t: LONE JACK PROPERTY PLATE Project No. s F -661 GRAIN SIZE DISTRIBUTION CURVES 11 CONSOLIDATION TEST CURVE Normal Pressure to Kips /sq. ft. 02 0.3 0.5 0.7 1 0 2.0 4.0 8.0 1 2 3 4 5 6 7 i �v 8 i " 9 C 0 e 10 11 12 13 14 15 Project LONE JACK .l ob N o, 661 Plate No. Date 1 -13 -8 Inundation Sample Location ' �� ��� ■ �� �+'�►'��� l/JC. 11080 Roselle Sveet, Suite A • San Diego, CA 92121 CONSOLIDATION VEST CURVE Normal Pressure to Kips /sq. (t. I 0.1 0.3 0.5 0.7 1 0 2.0 4.0 8.0 i - 6 I - 5 I -4 -3 i -2 I -1 ! 0 i 0 '_ 1 c� 2 ae ( 3 I 4 5 6 I I LONE JACK Project Job No. 6 61 Plate No. 13 Date 1 -13 -87 ® Inundation Sample Location " 11080 Roselle Street. Suite A • San Diego. CA 92121 r + CONSOLIDATION TEST CURVE Normal Pressure to Kips /sq. (t. I 0.1 0.3 0.5 0.7 1 0 2.0 4.0 8.0 I -4 I -3 2 _1 I 0 I 1 I 2 c 0 1 � 3 v o C 4 C 0 U ae1 S I 6 7 I 8 I 9 LONE JACK �1 P roject Job No. 661 Plate No. 14 I ate 1 -13 -87 Inundation Sample Location B - 6 AT 6.5 .w.ii�. <. .' a ,.. f/1 ` � \Q 11000 Roselle Street. Suite A • San Diego, CA 92121 CONSOLIDATION 'VEST CURVE Normal Pressure In Kips /sq. ft. 0.1 0.3 0.5 0.7 1 0 2.0 4.0 8.0 I -1 I 0 1 2 I 3 I 4 I 5 L I 0 b i 01 7 C ae I 8 I 9 I I LONE JACK roject Job No. 661 Plate No. 15_ Date 1 -13 -87 8-7.6 AT 10' Inundation Samp Location 11060 Roselle Street, Suite A • San Diego. CA 92121 r PASCO ENGINEERING, INC. 535 NORTH HIGHWAY 101, SUITE A SOLANA BEACH, CA 92075 (619) 259 -8212 WAYNE A. PASCO FAX (619) 2544812 R.C.E. 29577 September 20, 1995 PE 379F City of Encinitas Engineering Department 505 S. Vulcan Ave. Encinitas, CA, 92024 -3633 Attn: Blair Knoll Re: Grading Plan Hydrology for Lot 3, Map 12694. Wiegand residence. Dear Mr. Knoll, The purpose of this letter is to address the impacts of storm runoff on the proposed grading project located at 1060 Wiegand Street. The grading as proposed for the above mentioned single family residence intercepts the natural sheet flow drainage that currently exists on the site. The total drainage area effected by the proposed grading is approximately 6.15 ac. The drainage area is split into two separate basins by the proposed brow ditch at the top of the proposed cut slope. (See node 1.11, exhibit "A ") The storm runoff produced by the larger of the two basins is intercepted, contained and conveyed to the existing flowline of the AC dike in Wiegand Street by rock lined ditch, and driveway as shown on the above mentioned Grading Plan; the historic point of discharge. The storm runoff generated by the other basin is intercepted, contained and conveyed in the same type of ditch around the proposed pad to the north and discharged into a large Rip -Rap energy dissipater where it is allowed to slow to non erosive velocities and spread out to prevent erosion damage to the adjacent property. All pad drainage is contained and conveyed in an earthen, grass lined swale as shown on the Grading Plan mentioned above. The Hydrology and Hydraulic calculations attached show that the drainage improvements as proposed on this Grading Plan are adequate to intercept, contain and convey Qioo to the historic point of discharge. If you have any questions or comments, please do not hesitate to contact our offices. Very truly yours, PASCO ENGINEERING, INC. ��p QRF ASpN9� LJ ay- �aOC -) y �� 'i Fya Car Wayne Pasco, RCE 29577 3 President N0.29577 WP /ms cmv OF CAI���� ******************************************** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** RATIONAL METHOD HYDROLOGY COMPUTER PROGRAM PACKAGE Reference: SAN DIEGO COUNTY FLOOD CONTROL DISTRICT 1985,1981 HYDROLOGY MANUAL (c) Copyright 1982 -92 Advanced Engineering Software (aes) Ver. 1.3A Release Date: 3/06/92 License ID 1388 Analysis prepared by: Pasco Engineering, Inc. 535 North Highway 101, Suite A Solana Beach, CA. 92075 Ph. (619) 259 -8212 fax: (619) 259 -4812 * * * * * * * * * * * * * * * * * * * * * * * * ** DESCRIPTION OF STUDY 100 YEAR HYDROLOGY ANALYSIS WIEGAND PE 652 * SEE EXHIBIT " A " ******************************************** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** FILE NAME: 652A.DAT TIME /DATE OF STUDY: 9:20 9/20/1995 -------------------------------------------------- USER SPECIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION: --------------------------------------------------- 1985 SAN DIEGO MANUAL CRITERIA USER SPECIFIED STORM EVENT(YEAR) = 100.00 6 -HOUR DURATION PRECIPITATION (INCHES) = 3.000 SPECIFIED MINIMUM PIPE SIZE(INCH) = 6.00 SPECIFIED PERCENT OF GRADIENTS(DECIMAL) TO USE FOR FRICTION SLOPE _ .95 SAN DIEGO HYDROLOGY MANUAL "C"- VALUES USED NOTE: ONLY PEAK CONFLUENCE VALUES CONSIDERED * ******************************************* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** FLOW PROCESS FROM NODE 1.11 TO NODE 1.10 IS CODE = 21 ------------------------------------------------ » »> RATIONAL METHOD INITIAL SUBAREA ANALYSIS ««< ------------------------------------------ ------------------------- SOIL CLASSIFICATION IS "D" - - - - -_ RURAL DEVELOPMENT RUNOFF COEFFICIENT = .4500 NATURAL WATERSHED NOMOGRAPH TIME OF CONCENTRATION WITH 10- MINUTES ADDED = 12.98(MINUTES) INITIAL SUBAREA FLOW- LENGTH = 860.00 UPSTREAM ELEVATION = 325.00 DOWNSTREAM ELEVATION = 200.00 ELEVATION DIFFERENCE = 125.00 100 YEAR RAINFALL INTENSITY(INCH /HOUR) = 4.271 SUBAREA RUNOFF(CFS) = 6.27 OTAL AREA(ACRES) = 3.26 TOTAL RUNOFF(CFS) = 6.27 ******************************************** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** - FLOW PROCESS FROM NODE 1.10 TO NODE 1.00 IS CODE = 4 ------------------------------------------------ » »> COMPUTE PIPEFLOW TRAVELTIME THRU SUBAREA ««< » »> USING USER - SPECIFIED PIPESIZE« «< DEPTH OF FLOW IN 24.0 INCH PIPE IS 5.4 INCHES PIPEFLOW VELOCITY(FEET /SEC.) = 11.9 UPSTREAM NODE ELEVATION = 200.00 DOWNSTREAM NODE ELEVATION = 177.00 FLOWLENGTH(FEET) = 260.00 MANNING'S N = .015 GIVEN PIPE DIAMETER(INCH) = 24.00 NUMBER OF PIPES = 1 PIPEFLOW THRU SUBAREA(CFS) = 6.27 TRAVEL TIME(MIN.) _ .36 TC(MIN.) = 13.35 ********************************************* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** FLOW PROCESS FROM NODE 1.10 TO NODE 1.00 IS CODE = 8 ----------------------------------------------- » » >ADDITION OF SUBAREA TO MAINLINE PEAK FLOW« «< 100 YEAR RAINFALL INTENSITY(INCH /HOUR) = 4.196 SOIL CLASSIFICATION IS "D" RURAL DEVELOPMENT RUNOFF COEFFICIENT = .4500 SUBAREA AREA(ACRES) = 1.19 SUBAREA RUNOFF(CFS) = 2.25 TOTAL AREA(ACRES) = 4.45 TOTAL RUNOFF(CFS) = 8.51 TC(MIN) = 13.35 FLOW PROCESS FROM NODE 2.11 TO NODE 2.10 IS CODE = 21 ----------------------------------------------- » » >RATIONAL METHOD INITIAL SUBAREA ANALYSIS « «< ---------------------------------------------- ------------------------------- SOIL CLASSIFICATION IS "D" - - -- RURAL DEVELOPMENT RUNOFF COEFFICIENT = .4500 NATURAL WATERSHED NOMOGRAPH TIME OF CONCENTRATION WITH 10- MINUTES ADDED = 12.40(MINUTES) INITIAL SUBAREA FLOW - LENGTH = 740.00 UPSTREAM ELEVATION = 325.00 DOWNSTREAM ELEVATION = 185.00 ELEVATION DIFFERENCE = 140.00 100 YEAR RAINFALL INTENSITY(INCH /HOUR) = 4.400 SUBAREA RUNOFF(CFS) = 2.73 TOTAL AREA(ACRES) = 1.38 TOTAL RUNOFF(CFS) = 2.73 ********************************************* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** LOW PROCESS FROM NODE 2.10 TO NODE 2.00 IS CODE = 4 -------------------------------------------------- »>>COMPUTE PIPEFLOW TRAVELTIME THRU SUBAREA« «< »>>USING USER - SPECIFIED PIPESIZE ««< DEPTH OF FLOW IN 24.0 INCH PIPE IS 3.4 INCHES PIPEFLOW VELOCITY(FEET /SEC.) = 10.0 UPSTREAM NODE ELEVATION = 185.00 DOWNSTREAM NODE ELEVATION = 174.00 FLOWLENGTH(FEET) = 100.00 MANNING'S N = .015 GIVEN PIPE DIAMETER(INCH) = 24.00 NUMBER OF PIPES = 1 PIPEFLOW THRU SUBAREA(CFS) = 2.73 TRAVEL TIME(MIN.) _ .17 TC(MIN.) = 12.57 ******************************************** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** FLOW PROCESS FROM NODE 2.10 TO NODE 2.00 IS CODE = 8 ------------------------------------------- » » >ADDITION OF SUBAREA TO MAINLINE PEAK FLOW « «< 100 YEAR RAINFALL INTENSITY(INCH /HOUR) = 4.362 SOIL CLASSIFICATION IS "D" RURAL DEVELOPMENT RUNOFF COEFFICIENT = .4500 SUBAREA AREA(ACRES) _ .32 SUBAREA RUNOFF(CFS) _ .63 TOTAL AREA(ACRES) = 1.70 TOTAL RUNOFF(CFS) = 3.36 TC(MIN) = 12.57 END OF STUDY SUMMARY: PEAK FLOW RATE(CFS) = 3.36 Tc(MIN.) = 12.57 TOTAL AREA(ACRES) = 1.70 END OF RATIONAL METHOD ANALYSIS ******************************************** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** HYDRAULIC ELEMENTS - I PROGRAM PACKAGE (C) Copyright 1982 -92 Advanced Engineering Software (aes) Ver. 3.1A Release Date: 2/17/92 License ID 1388 Analysis prepared by: PASCO ENGINEERING 535 NORTH HWY 101, SUITE A SOLANA BEACH, CA. 92075 PHONE: (619) 259 -8212 FAX (619) 259 -4812 ------------------------------------------------------------ TIME /DATE OF STUDY: 9:38 9/20/1995 * * * * * * * * * * * * * * * * * * * * * * * * ** DESCRIPTION OF STUDY * * * * * * * * * * * * * * * * * * * * * * * * ** CAPACITY CHECK FOR ROCK LINED BROW DITCH PER D -75 (MODIFIED) NODE * ****** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** **** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** ******************************************** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** » >PIPEFLOW HYDRAULIC INPUT INFORMATION «« --------------------------------------------------------- PIPE DIAMETER(FEET) = 2.000 PIPE SLOPE (FEET /FEET) _ .0500 PIPEFLOW(CFS) = 6.30 MANNINGS FRICTION FACTOR = .040000 '/A)/Al' ----------------------------------- -------------------- CRITICAL -DEPTH FLOW INFORMATION: ------------------------------------------ CRITICAL DEPTH(FEET) _ .89 CRITICAL FLOW AREA(SQUARE FEET) = 1.348 CRITICAL FLOW TOP- WIDTH(FEET) = 1.988 CRITICAL FLOW PRESSURE + MOMENTUM(POUNDS) = 88.50 CRITICAL FLOW VELOCITY(FEET /SEC.) = 4.673 CRITICAL FLOW VELOCITY HEAD(FEET) _ .34 CRITICAL FLOW HYDRAULIC DEPTH(FEET) _ .68 CRITICAL FLOW SPECIFIC ENERGY(FEET) = 1.23 NORMAL -DEPTH FLOW INFORMATION: ------------------------------------------------ NORMAL DEPTH(FEET) _ .86 FLOW AREA(SQUARE FEET) = 1.29 FLOW TOP- WIDTH(FEET) = 1.980 FLOW PRESSURE + MOMENTUM(POUNDS) = 88.66 FLOW VELOCITY(FEET /SEC.) = 4.886 FLOW VELOCITY HEAD(FEET) _ .371 HYDRAULIC DEPTH(FEET) _ .65 FROUDE NUMBER = 1.067 SPECIFIC ENERGY(FEET) = 1.23 * * * * * * * * * * * * * * * * * * * * * * * * ** DESCRIPTION OF STUDY * * * * * * * * * * * * * * * * * * * * * * * * ** VELOCITY CHECK FOR ROCK LINED DITCH PER D -75 (MODIFIED) 100 YEAR STORM SEE EXHIBIT " A " ,:CUN - 0 92NEj¢sl,/ djQ.dM ***************************** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** * * * * * * * * * ** ******************************************** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** » >PIPEFLOW HYDRAULIC INPUT INFORMATION«« --------------------------------------------------------------------------- PIPE DIAMETER(FEET) = 2.000 PIPE SLOPE(FEET /FEET) _ .2000 /LI�- Se- PIPEFLOW(CFS) = 6.60 MANNINGS FRICTION FACTOR = .040000 — � ,�Q'.x 'L / .(J/ .tld,-- -------- - - - - -- CRITICAL -DEPTH FLOW INFORMATION: --------------------------------------------------------------------------- CRITICAL DEPTH(FEET) _ .91 CRITICAL FLOW AREA(SQUARE FEET) = 1.392 CRITICAL FLOW TOP- WIDTH(FEET) = 1.992 CRITICAL FLOW PRESSURE + MOMENTUM(POUNDS) = 93.97 CRITICAL FLOW VELOCITY(FEET /SEC.) = 4.743 CRITICAL FLOW VELOCITY HEAD(FEET) _ .35 CRITICAL FLOW HYDRAULIC DEPTH(FEET) _ .70 CRITICAL FLOW SPECIFIC ENERGY(FEET) = 1.26 --------------- - - - -- NORMAL -DEPTH FLOW INFORMATION: --------------------------------------------------------------------------- NORMAL DEPTH(FEET) _ .61 FLOW AREA(SQUARE FEET) _ .81 FLOW TOP- WIDTH(FEET) = 1.840 FLOW PRESSURE + MOMENTUM(POUNDS) = 117.37 N`' .FLOW VFTnrTTV (FF.F.T f G � = 8.180 �--- - • i /V�. G J94k /A40 FLOW VELOCITY HEAD(FEET) = 1.039 HYDRAULIC DEPTH(FEET) _ .44 FROUDE NUMBER = 2.177 SPECIFIC ENERGY(FEET) = 1.65 -�- use X/o. 2 454:�ell%A* ©. 5 OAP7 r1114& w11 oA)e Z.4ye �"40 4. S..D . * * * * * * * * * * * * * * * * * * * * * * * ** DESCRIPTION OF STUDY * * * * * * * * * * * * * * * * * * * * * * * * ** CAPACITY CHECK FOR ROCK LINED DITCH PER D -75 (MODIFIED) 100 YEAR STORM SEE EXHIBIT " A " NODE(2.],J ******************************************** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** » >PIPEFLOW HYDRAULIC INPUT INFORMATION «« --------------------------------------------------------------------------- PIPE DIAMETER(FEET) = 2.000 PIPE SLOPE (FEET /FEET) _ . 0200 --Ow PIPEFLOW(CFS) = 2.73 MANNINGS FRICTION FACTOR = .040000 -V' GINIV4 --------------------------- - - - - -- CRITICAL -DEPTH FLOW INFORMATION: --------------------------------------------------------------------------- CRITICAL DEPTH(FEET) = .58 CRITICAL FLOW AREA(SQUARE FEET) _ .748 CRITICAL FLOW TOP- WIDTH(FEET) = 1.811 CRITICAL FLOW PRESSURE + MOMENTUM(POUNDS) = 30.50 CRITICAL FLOW VELOCITY(FEET /SEC.) = 3.648 CRITICAL FLOW VELOCITY HEAD(FEET) = .21 CRITICAL FLOW HYDRAULIC DEPTH(FEET) = .41 CRITICAL FLOW SPECIFIC ENERGY(FEET) = .78 ----------------------------- ------ NORMAL -DEPTH FLOW INFORMATION: --------------------------------------------------------------------------- NORMAL DEPTH(FEET) = .70 ,z �{ O FLOW AREA(SQUARE FEET) _ .98 FLOW TOP- WIDTH(FEET) = 1.908 FLOW PRESSURE + MOMENTUM(POUNDS) = 32.56 FLOW VELOCITY(FEET /SEC.) = 2.789 FLOW VELOCITY HEAD(FEET) = .121 HYDRAULIC DEPTH(FEET) = .51 FROUDE NUMBER = .686 SPECIFIC ENERGY(FEET) .82 * * * * * * * * * * * * * * * * * * * * * * * * ** DESCRIPTION OF STUDY * * * * * * * * * * * * * * * * * * * * * * * * ** VELOCITY CHECK FOR ROCK LINED DITCH PER D -75 (MODIFIED) 100 YEAR STORM SEE EXHIBIT " A " NODE ******************************************** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** » >PIPEFLOW HYDRAULIC INPUT INFORMATION«« ------------------------------------------------- - - - -�- --------------- - - -- PIPE DIAMETER(FEET) = 2.000 PIPE SLOPE(FEET /FEET) _ .2000 PIPEFLOW(CFS) = 2.73 MANNINGS FRICTION FACTOR = .040000 CRITICAL -DEPTH FLOW INFORMATION: --------------------------------------------------------------------------- CRITICAL DEPTH(FEET) = .58 CRITICAL FLOW AREA(SQUARE FEET) _ .748 CRITICAL FLOW TOP- WIDTH(FEET) = 1.811 CRITICAL FLOW PRESSURE + MOMENTUM(POUNDS) = 30.50 CRITICAL FLOW VELOCITY(FEET /SEC.) = 3.648 CRITICAL FLOW VELOCITY HEAD(FEET) = .21 CRITICAL FLOW HYDRAULIC DEPTH(FEET) = .41 CRITICAL FLOW SPECIFIC ENERGY(FEET) = .78 NORMAL -DEPTH FLOW INFORMATION: --------------------------------------------------------------------------- NORMAL DEPTH(FEET) = .39 FLOW AREA(SQUARE FEET) _ .43 FLOW TOP- WIDTH(FEET) = 1.584 FLOW PRESSURE + MOMENTUM(POUNDS) = 37.89 FLOW VELOCITY ( FEET / SEC . ) = 6.3 3 7 FLOW VELOCITY HEAD(FEET) = .624 HYDRAULIC DEPTH(FEET) = .27 FROUDE NUMBER = 2.142 SPECIFIC ENERGY(FEET) = 1.01 A) eoo �exl 3 y .�8ir/f f�c ,S D !�'d D -7,57. va ntna N �� �a b n 0. y-a vs a w ;7 3 VI VI VI OAN"'N N A 0 O. K CT S { -q .1 - - ...I a >r A N. 0 N 0 0 0 +_o cQCCCO O O O O i $ o a > o m -I. b O{ 1 1 N G' Vf n — A N d 0 an d ..� A b rn a -i a -1 n 3 . 0 a tp -4 omm � oo $e o o'o � g 1 a - 0+f� O m �� 0 . n N C 3� d O b 0 O O ' Al A + O — O n A C m O Q �O Vt ff G7 3 O nab - � 00 '1 - f X yN1 pp QQ D Z 7 b b 3 I 7 N N fTl O to a —� -1 0 0 S CZ 1 a; Q m -F l -0 37 07 A 3 N t 41 •• T O VI _ y m m - 0 0 a N pO I �\ O� 7 A ; ; M CL 1 AS— M Z O x 0 e a >•�� v .e 7 N O V1 O b O 7 C i !D - N 1� 0 1 000 h 1 �' '..m a i O M 3 8 7 N Ll 0 b .y. o .� f7 b O N O o 0 — W �1 O 7 B C' tO f N O Z ' a 3 1 n G u = �1 -fu - O I vQ = u I T 0 '� d �0— c o N ch 1 I 1 \m Cm - 7 cr 10 M O) J 1 O v �• tv 00 u w — x m� b �' 0 O C7 p � C O N S I IG A to A. A• N b A 1 C'0 m + I N 7r w u 7r 10 < a 0 la S ? NI a t.l N a —� Cn O N u n 1 b s 7 1 -0 b O O O T � A M w -7r Cp o C �i 0 —0 N -1 N \ A N O a O O+ A 3 = a 3 s s S A• 1 m y m O 3. 7 —� �.b J 7 ..a . ap co N 0 fta a a O O O b -+c O 26 1 1 U N On N N 0 o Q+ 3 O + O O 0 L4 'a — ...� C1 — ac O 0 0 C[ T N V1 N a , N b 0 b C b b 1 I CL a a o. i A Amlh� Geotechnics Incorporated Principals: Anthony F. Belfast Michael P. Imbriglio December 1, 1995 W. Lee Vanderhurst ' ' Bruce D. Wiegand, Inc. Project No. 0007 - 003 -04 1060 Wiegand Street Doc. #5 -0610 Olivenhain, California 92024 ' SUBJECT: AS- GRADED GEOTECHNICAL REPORT Testing & Observation of Earthwork Construction t Copper Creek Estates, Lot 3 Encinitas, California Gentlemen: This report summarizes the results of the testing and observation services performed by t Geotechnics Incorporated during grading operations at Lot 3 of the Copper Creek Estates Development. Grading for this project was conducted by Bert Sims Grading. Our geotechnical ' services were performed between November 16 and October 28, 1995. 1.0 PURPOSE AND SCOPE OF SERVICES 1 This report and the associated geotechnical services were performed in accordance with the ' verbal authorization given by Mr. Bruce Wiegand on October 17, 1995. Field personnel were provided for this project in order to test and observe site grading operations. These observations ' and tests assisted us in developing professional opinions regarding whether or not earthwork was conducted in accordance with the project specifications and geotechnical recommendations. Our services did not include supervision or direction of the actual work of the contractor, his ' employees, nor agents. Our services did include the following. • Observation of the preparation of the existing ground in order to determine whether existing colluvium was removed and compacted in accordance with the geotechnical recommendations. • Performing suitable field and laboratory tests on fill to support geotechnical ' recommendations and conclusions. P.O. Box 26500 -224 • San Diego California • 92196 Phone (619) 536 -1000 • Fax (619) 536 -8311 ' Bruce D. Wiegand, Inc. Project No. 0007 - 003 -04 December 1, 1995 Doc. #5 -0610 Page 2 • Preparation of daily field reports summarizing the day's activity with regard to earthwork, ' and documenting hours spent in the field by our technicians. • Preparation of this report which summarizes site preparation, field and laboratory test results, fill placement, and the compaction operations. ' 2.0 SITE DESCRIPTION ' The site is located within the coastal section of the Peninsular Range Geomorphic Province. The coastal section is characterized by relatively subdued landforms underlain by marine sediments. ' Prior to grading, the subject site was underlain by weathered undifferentiated units of the Del Mar and Friars Formations, as well as by variable thicknesses of colluvium and topsoil. ' The subject site consists of Lot 3 of the Copper Creek Estates in the community of Olivenhain, California. The site is bordered by Wiegand Street on the south, a developed residential lot on ' the east, and undeveloped lots on the north and west. A schematic layout of the site, including the approximate location of the density tests taken by Geotechnics during site grading, is presented in the Site Plan, Figure 1. 3.0 GRADING OPERATIONS ' Grading of the site was performed using typical grading techniques with heavy earth-moving equipment. The equipment used for compaction consisted of a paddlewheel scraper, an 814 sheepsfoot wheel compactor, a D6 finish dozer, and a water hose for moisture conditioning. Grading operations included removal of loose, weathered colluvium material beneath the eastern ' portion of the main structure, and replacement as compacted fill. The western half of the structure including the basement was founded entirely on formational material. Post - tensioned ' slabs will be used to mitigate potential differential heave and settlement, incorporating the design parameters given in Section 4.0. The colluvium material was found to be highly expansive, as indicated by the test results presented in Figure B -1. Consequently, all fill placed beneath the ' residence was moisture conditioned by compacting well over optimum. The minimum recommended compaction was 87 percent, in order to reduce the potential for expansion. The ' fill slopes on site were constructed by overexcavating approximately three to four feet of material beneath the base of the slope in order to provide a compacted fill key. t Geotcchnics locu►poiatcd polejodjO3LIJ PLIL ,/ • .••• / V O - COO - LOOO'ON 103rOUd NVId 311S Z b t Ir r � I' � ,�� � • � � X11 C J II .y Y ' Bruce D. Wiegand, Inc. Project No. 0007 - 003 -04 December 1, 1995 Doc. #5 -0610 ' Page 3 ' The maximum densities and optimum moisture contents of selected fill materials are shown in Figure B -1 of the appendix, "Laboratory Test Results ". The maximum densities and optimum moistures of the soils were determined in the laboratory by ASTM method D1557, (Modified ' Proctor). The on -site fill soils generally consisted of a fine to medium grained clayey sand (SC). ' In -place moisture and density tests were made in accordance with ASTM D 2922 and D 3017 (Nuclear Gauge Method). The results of these tests are tabulated in Figure C -1 in the appendix, "Field Density Test Results ". The actual test locations are shown on the Site Plan, Figure 1. The locations and elevations indicated for the tests are based on field survey stakes and estimates from the grading plan topography, and should only be considered rough estimates. The estimated locations and elevations should not be utilized for the purpose of preparing cross sections showing test locations, or in any case, for the purpose of after - the -fact evaluating of the sequence of fill placement. 4.0 GEOTECHNICAL RECOMMENDATIONS The slab subgrade soils include highly g y clayey sand, as Indicated by the test results presented in Figure B -1. The soils were moisture conditioned during grading in order to decrease expansion. However, we recommend that a structurally designed, post- tensioned slab -on -grade be used to mitigate an additional effects of soil expansion. We recommend the following parameters, based on criteria of the Post - Tensioning Institute. ' Edge Moisture Variation, e Center Lift: 6.0 feet Edge Lift: 3.0 feet ' Differential Swell, Y Center Lift: 5.5 inches ' Edge Lift: 1.1 inches Differential Settlement: 0.5 inches ' Allowable Bearing Capacity at Slab Subgrade: 2,000 lbs /ft Gcotcchnics Inc01ho1.1tcd ' Bruce D. Wiegand, Inc. Project No. 0007 - 003 -04 December 1, 1995 Doc. #5 -0610 ' Page 4 ' 5.0 GEOTECHNICAL EVALUATION In our opinion, grading and compaction of the site was performed in general accordance with the ' intent of the project geotechnical recommendations, project specifications, and with the requirements of the City of Encinitas. Based upon our observations and testing, it is our ' professional opinion that fill soils were placed in substantial accordance with the compaction criteria of 87 percent of the maximum density (ASTM D1557). The conclusions and recommendations contained herein are based on our observations and testing performed between ' November 16 and October 28, 1995. No representations are made as to the quality and extent of materials not observed. 6.0 LIMITATIONS ' Our services were performed using the degree of care and skill ordinarily exercised, under similar circumstances, by reputable soils engineers and geologists practicing in this or similar localities. ' No other warranty, expressed or implied, is made as to the conclusions and professional advice included in this report. ' The samples taken and used for testing, the observations made, and the in -place field testing performed are believed representative of the project; however, soil and geologic conditions can j vary significantly between tested or observed locations. ' This report is issued with the understanding that it is the responsibility of the owner, or of his representative, to ensure that the information and recommendations contained herein are brought to the attention of the architect and engineer for the project and incorporated into the plans, and ' the necessary steps are taken to see that the contractor and subcontractors carry out such recommendations in the field. ' This firm does not ractice or consult in the e field of safety engineering. We do not direct the ' contractor's operations, and we cannot be responsible for other than our own personnel on the site; therefore, the safety of others is the responsibility of the contractor. The contractor should notify the owner if he considers any of the recommended actions presented herein to be unsafe. ' The findings of this report are 9 p valid as of the present date. However, changes in the conditions of a property can occur with the passage of time, whether they be due to natural processes or the works of man on this or adjacent properties. In addition, changes in applicable or appropriate ' Geo(CCllllics Incolponited ' Bruce D. 1 Inc. December r 1, Project No. 0007 - 003 -04 , 19 95 5 19 Doc. #5 -0610 ' Page 5 standards may occur, whether they result from legislation or the broadening of knowledge. Accordingly, the findings of this report may be invalidated wholly or partially by changes outside our control. Therefore, this report is subject to review and should not be relied upon after a period of three years. ' GEOTECHNICS INCORPORATED ' Anthony F. Belfast, P.E. 40333 Principal .at F ' AFB /maf - NO. C040 279 Distribution: (4) Addressee ' Gcotcchnics Incolpon►tcd ' APPENDIX A REFERENCES American Society for Testing and Materials, 1992, Annual Book of ASTM Standards, Section 4 Construction Volume 04.08 Soil and Rock; Dimension Stone; Geos nthetics, ASTM, ' Philadelphia, PA, 1296 p. ' ICG Incorporated, June 8, 1989, Slope stability evaluation, 8 lot subdivision, Lone Jack Road, Encinitas, California, Job No. 04- 3867- 002- 01 -00, Log No. 9 -1721. Santa Fe Soils, Inc., January 12, 1987, Geologic and soils engineering investigation, 25 acre hillside parcel, Lone Jack Road, Encinitas, California, SF -661. ' Gcotedmics Incoijx►ritcd 1 APPENDIX B LABORATORY TESTING ' Selected representative samples of soils encountered were tested using est methods o 9 f the American Society for Testing and Materials, or other generally accepted standards. A brief ' description of the tests performed follows: ' Classification Soils were classified visually according to the Unified Soil Classification System. Visual classification was supplemented by laboratory testing of selected samples and clas- sification in accordance with ASTM D2487. Maximum Density Optimum Moisture The maximum density and optimum moisture for ' representative soil samples were determined by using test method ASTM D1557, modified Proctor. The test results are summarized in Figure B -1. ' Expansion Index: The expansion potential of selected soils was characterized by using the test method ASTM D 4829. Figure B -2 provides the results of the tests. ' Ccotccluiics Incolponatcd MAXIMUM DENSITY TEST RESULTS (ASTM D1557) Sample Description ;Density Dry Moisture ' No. Content f) N 1 Dark brown fine to medium grained clayey sand (SC). .3 13.5 ' 2 Brown fine to medium rained clayey a sand SC . 114.5 16.0 EXPANSION TEST RESULTS (ASTM D4829) SAMPLE EXPANSION INDEX Sample #1 gg ' UBC TABLE NO. 29 -C, CLASSIFICATION OF EXPANSIVE SOIL EXPANSION INDEX POTENTIAL EXPANSION 0 -20 Very low 21 -50 Low 51 -90 Medium ' 91 -130 High Above 130 Very high Laboratory Test Results Project No. 0007 - 003 -04 a ieoiccllr>>cs 1 11 CO 1 O r it t e d Copper Creek Estates, Lot 8 Document No. 5 -0610 ' Bruce D. Wiegand, Inc. Figure B -1 1 APPENDIX C FIELD TEST RESULTS ' - Elevations and locations of field tests were determined by hand level and pacing relative to field ' staking done by others. -The precision of the field density test and the maximum dry density test is not exact and ' variations should be expected. For example, the American Society for Testing and Materials has recently researched the precision of ASTM Method No. D1557 and found the accuracy of the ' maximum dry density to be plus or minus 4 percent of the mean value and the optimum moisture content to be accurate to plus or minus 15 percent of the mean value; the Society specifically states the "acceptable range of test results expressed as a percent of mean value" is the range ' stated above. In effect, an indicated relative compaction of 90 percent has an acceptable range of 86.6 to 92.8 percent based on the maximurn dry density determination. The precision of the field density test ASTM D1556 has not yet been determined by the American Society for Testing and Materials; however, it must be recognized that it also is subject to variations in accuracy. Ceotechnics Incorporated Test Test Elevation/ Soil Max. Dry Moisture Dry Relative Required Retest Test ' No. Date Location Type Density Content Density Compaction Compaction Number Method IN [Pct] [ %) [pct) [ %] [ %) 1 11/16/95 173 1 118.3 19.8 107.6 91 ' 2 11/16/95 174 1 118.3 21.6 105.8 89 88 NU 88 NU 3 11/17/95 176 1 118.3 23.2 103.9 88 88 4 11/17/95 177 1 118.3 20.8 105.3 89 NU ' 5 11/17/95 178 1 88 NU 118.3 18.4 106.0 90 88 NU 6 11/17/95 179 1 118.3 24.0 103.6 88 7 11/20/95 180 2 88 NU 114.5 22.2 100.3 88 88 NU ' 8 11/20/95 181 2 114.5 19.8 1012 88 9 11/20/95 181 2 114.5 20.6 101.7 89 88 NU 88 NU 10 11/21/95 182 2 114.5 21.4 101.0 88 88 NU 11 11/22/95 182 2 114.5 20.8 103.2 90 ' 12 11/23/95 183 2 114.5 19.9 103.9 91 88 NU 88 NU 13 11/22/95 184 2 114.5 19.8 102.8 90 14 11/22/95 184 2 114.5 20.1 101.7 88 NU 15 9 11/28/95 180 2 114.5 17.1 9 87 88 NU ' 88 slope NU LEGEND: AC = Asphaltic Concrete JT = Joint Trench e= Base NU = Nuclear Gauge CG = Curb & Gutter SC = Sand Cone FF = Finish Floor SG = Subgrade ' FG = Finish Grade SS = Sanitary Sewar ' i_G e o t e c )1 n i c s CompactionTest Results Project No. 0007 - 003 -04 I n c o r p o r a t e d Copper Creek Estates Lot 3 Doc. # 5 -0606 ' Bruce Wiegand Incorporated Figure C -1 may, _ f • � 1 'y `` / L+ � ' + i �� . ..� 1 t r i , . �' , .r ''. �.- ' ter__._ �.. ...�..- _ .. • . .,w t r . _ � _ ... _ 1. -- e 91 . 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