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HomeMy WebLinkAbout3151; Palomar Airport Road Widening; Seepage Investigation Palomar Airport Road Stations 43 - 51Widening; 1989-06-29American Engineering Laboratories Inc. M) 3151 m SEEPAGE INVESTIGATION PALOMAR AIRPORT ROAD STATIONS 43+00 - 51+00 GARLSBAD, CALIFORNIA PREPARED FORI CITY OF CARLSBAD MUNICIPAL PROJECT DIVISION 2075 LAS PALMAS DRIVE CARLSBAD, CALIFORNIA m San Diego Corona Modesto Yucca Valley JOB NO.I 1-172.1 JUNE 29, 1989 American Engineenng Laboratories. Inc. Corporate Office: 7940 Arjons Dr.. Suite A, San Diego, CA 92126 (619) 695-3730 350 South Maple St., Unit K, Corona, CA 91720 (714) 272-4230 515 Galaxy Way, Modesto, CA 95356 (209) 576-0813 58945 Business Center Dr., Unit A. Yucca Valley. CA 92284 (619) 228-1754 CITY OF CARLSBAD Municipal Project Division 2075 Las Palmas Drive Carlsbad, CA 92009 JUNE 29, 1989 JOB NO.: 1-172.1 ATTENTION: SUBJECT: Mr, Al Virgilio SEEPA6E_INVESTIGATigN PALOMAR AIRPORT ROAD STATIONS 43+00 - 51+00 CARLSBAD, CALIFORNIA Gentlemen: Pursuant to your request, we have performed a Seepage Investi- gation of the aforementioned subject site. Our services included a visual reconnaissance of the site, exploratory borings, geologic mapping, and preparation containing our conclusions and of site conditions. of this report recommendations for mitigation 1.0 SITE DESCRIPTION Saturated ground conditions along Palomar Airport Road were observed by personnel of the City of Carlsbad and our geologist. The seepage was present at the base of a recentiy constructed slope between stations 47+75 and 49+25. At the time of the investigation, the north side of the road alignment had been constructed to subgrade elevations. Utility improvements were buried in the curb area, with sewer and water lines buried in the road area. The road alignment lies along the north side of Canyon de Las Encinas at an elevation of approximately 70 feet above Mean Sea Level (MSL). The road subgrade ranges in height from 10 to 20 feet above the canyon drainage. Over 400 acres of cultivated agricultural land lies north of the site and ranges in elevation from 70 t to 320 i feet (MSL). 2.0 SITE_INVESTIGATION surficial reconnais- conducted on May 30, Subsurface exploration was conducted with a mobile The site investigation, consisting of sance and subsurface exploration, was 1989. SEEPAGE INVESTIGATION PAGE 2 CITY OF CARLSBAD JOB NO.: 1172.1 PALOMAR AIRPORT ROAD JUNE 29, 1989 4-inch Solid Flite stem auger drilling rig. A total of 10 holes was bored in the area of the saturated ground conditions. The purpose of the borings was to evaluate the seepage conditions and to provide opinions and recommenda- tions regarding those conditions. The borings were completed to depths ranging from 1.0 to 10.0 feet below existing curb and road subgrades. Appendix B contains geologic logs of the borings. 3.0 GEgLOGIC_UNITS The surficial geology was mapped revealing the subject site is underiain by interbedded sandstones and claystones mapped as the Eocene Age Scripps and Del Mar Formations. Alluvial deposits of silt and clayey sands are present in the trans- verse drainages and the main Canyon de Las Encinas drainage. 3.1 SANDSTONE Sandstone found at the site ranged from clayey fine sand to poorly graded, medium grained sand. Local lenses of medium to coarse grained, well graded sand were present locally. The sanstones were generally found to be moist and medium dense to dense in consistency. The permeability for clayey to fine grained, poorly graded sands appears to be low, while the coarse grained, well graded sands generally are high to very high. 3.2 CLAYSTONE The claystones consisted of light brown to brown sandy clay that generally was dry to moist and very dense. These materials possess low permeability characteristics. 4.0 GROUNDWATER Saturated ground conditions were observed at the base of the cut slope, in the curb and street subgrade areas between stations 47+75 and 49+25. The saturation extended approxi- mately 5 feet above the curb elevation, and extended 5 to 10 feet south of the curb in the street subgrade. Standing water was observed by representatives of the City of Carlsbad prior to our evaluation. Borings 3, 4, 6, and 7 encountered groundwater at depths ranging from 2.1 to 7.6 feet below existing grades (elevations 68.04 to 61.71 MSL). Very moist to saturated conditions extended upward from the observed groundwater levels. SEEPAGE INVESTIGATION PAGE 3 CITY OF CARLSBAD JOB NO.: 1172.1 PALOMAR AIRPORT ROAD JUNE 29, 1989 5.0 CgNCLUSIONS_AND_RECOMMENDATI Saturated ground conditions appear to be a result of a local perched groundwater table within the Eocene Age Scripps Formation, Permeability contrasts between the well-graded, coarse sandstone and fine-grained, clayey sandstones and claystones control the flow of local groundwater. Adjacent agricultural areas tend to provide a significant amount of recharge to the local groundwater system. The degree of saturation of the cut slope will depend on the amount and rate of groundwater recharge from the adjacent open agricultural areas. It is recommended that an appropriate drain system be installed at the toe of the cut slope to control the saturated ground conditions. Decreasing the ground saturation should enhance the gross stability of the cut slope and the performance of proposed street and curb improvements along Palomar Airport Road. The attached Figure 1 provides a sketch of the recommended cut-off drain system that should be constructed in the area of saturation. The approximate location of the drain is shown on Plate 2. 6.0 LIMITATIONS This report is based on, and limited to, a visual reconnais- sance and exploratory borings of the subject site. Our conclusions and recommendations are professional opinions. « These opinions have been derived in accordance with current standards of practice and no warranty is expressed or implied. We appreciate this opportunity to be of service to you on this project and look forward to a continued association on this and future projects. If you have any questions regarding this report, please contact us at your convenience. Respectfully submitted, AMERICAN ENGINEERING LABORATORIES, INC. m Steven N. Bradley, R55614 Geotechnical Department Manager SNB/vr/R4 APPENDIX mm Palomar airport road cut off drain 2:1 Cut Slope Bedrock min min 4* min 4* min 1.5' min -« Joint utilities trench Supac 5-P fabric or approved equal 4.5 ft minimum per lineal foot approved filter rock* 4" minimum perforated pipe** "5' Street subgrade 'water line *Drain material to meet following specifications or approved equal: **Approved pipe to be schedule 40 poly-vinyl-chloride (P.V.C.) or approved equal minimum crush strength 1000 psi Sieve size 1 1/2" r* 3/4" 3/8" no. 200 Percentage passing 68-100 5-40 0-17 0-7 0-3 RGURE 1 AMERICAN ENGINEERING UBORATORiES DATE Qosgavgn- 5/30/89 METHOD OF PHILLINC- 4" Beaver Rig LQCGED BY:_^ GROUND ELEVATION:_Zi:§L_ LOCATtON:I^EZ^^^ o a o Ui o a \u a b. .1* u. ul »-Zr i2< O < a o Ui 3 a 5 = so u Oo. 5S BORING NO L DESCRIPTION SOIL TEST 10- 15- 20- 25- 30- 35- SP MMXX: li^t brown, fiiie to mediun SAND, moist, slightly dense. Total Depth - 10' No groundwater eaicountered. jOa NO^ 1-172.1 LOG OF aOfllNG f iCuad; Bl AMERICAN ENGINEERING UBORATORIES ueTHon np no... .K.^. 4" Beaver Rig DATE Qnsgauen- 5/30/89 LOGGED BY:_GB_GHOUNO PLCVATIQN- 72.^' LncATini^.45 + 25 mLd-road 3 o o w 5 u o dm 3a. w t/l -* r^ Q < a 3 o 3 Si o = 20 u Oo. sis 5S BORING NO., SOIL TEST DESCRIPTION SP JJSE: 5- 10- 15- 20- 25- 30- 35- SC EECKOCK: light brown, fine to mediuni SAND, moist, loose. light greaiish vMte, fine to nedxum SAND, moist, msdiim dense, some clay balls. T.ight: green, clayey, fine to mediun SAND, moist, medium dense. Total Depth - 10 No groundvater encountered. joa no.: 1-172,1 LOG OF BORING ficuatL B2 AMERICAN ENGINEERING LABORATORIES DATE OQSEavED: LOGGED BY:_^ . 5/30/89 .GROUND PI ex/ATiQN' 69.71 i.nnATinw. Sta. 48 + 25 < o o o Um o o 3a. aui < 3 a —• O3 50 u Oa. < C is BORING NO., DESCRIPTION SOIL TEST 5- 10- 15- 20- 25- 30-1 35- SP a BEMXX: light tan to ;Mte, fine to msdiim SAND, moist, loose. At 3,3', grounAiHter light brwn sandy CLAY, very moist, very dense. Total Depth - 10 GEroundvater encountered at 3.3' JO a MO.: 1-172.1 LOG OF BORING ficuat; B-3 AMERICAN ENGINEERING LABORATORIES DATE nn«;Fauen- 5/30/89 METHOD np n»i.. iMn- 4" Beaver Rig LOGGED HR nnnuMn FLCV/ATIQN- fi9.61 LncATtnu. Sta. 48 + 25 (middle of road) < (A < rJ o o o u. •» ir Q c ^ 3a. r- ^ i2< aut < Ui 3 Q Oz SO o ao. o> Sis BORING NO. DESCRIPTION SOIL TEST 5- 10- 15- 20- 25- 30- 35- 40-4 SP SC SC CL 0 BEEMXK: light tan to vdiite, fine to medium SAND, moist, loose. light brown, fine to medium SAND with clay, moist, slightly dense. light brown clayey SAND, dry to moist very daise. Groundwater encountered at 7,9' \ „ Yellow brown sandy CLAY, dry to nrast, very fine grained. Total Efepth - 10' Groundwater encountered at 7.9' jOa no,: 1-172.1 LOG OF BORING AMERICAN ENGINEERING LABORATORIES DATE OQSEavED: METHOD OF nmi i iMr- 4 Beaver Rig LOGGED RV' GB GHQiiMP Pi cwATiQM' 70.08' LQCATinw Sta. 47 + 25 o o tk Ul I* O a w Qu CC ^ 3a. QUI < Ui —. Oz so u Qo. s:s 5S BORING NO., SOIL TEST DESCRIPTION SP 5- 10- 15- 20- SP 25- 30- 35- 40-J BEDROCK: Brown, fine SAND, moist, loose. light tan, fine to nEdium SAND, moist, loose. Total Depth - 4' No groundvater encountered. joa hO,: 1.172,1 LOG OF BORING |flCuati:B5 AMERICAN ENGINEERING UUaORATORlES DATE f>n«!FauPn. 5/30/89 LOGGED BY:_GE__CnOUND Pt e\/ATiQN- 70.08' LQCATiQM- Sta. 47+25 METHOD OF oniLLiNn- 4" Beaver RLg o o Ul o UJ rJ u o But u ik "» CC ^ 3a. < u. Ul t-Ui IL Ul o QWl -i w < z 3 a o o 3 O Uit §^ MU —• r— Oz u cco 0(L HS BORING NO. SOIL TEST DESCRIPTION 5- 10- 15- 20- SP 25- 30- 35- 40-J BECKOCK: Light yellow brown, fine to mediun SAND, dry to moist, loose. At 4', moist and traces of CLAY. At 7.6', groundvater encountered. Total Depth - 10 Groundvat^ encountered at 7.6' JO a NO,: 1,172.1 LOG OF BORING |fiCuat;B-6 AMERICAN ENGINEERING LABORATORIES uPTHon ng not. . .Mr.. 4' Beaver Rig OATE OQSEHVEO: LOGGED BY:_^ . 5/30/89 .GROUND PI ex/ATIQM' 70.14 LQCATlQMr Sta. 47 + 75 rm. 5 a Ui o u Ui u h. ICAI o u. O Ui EC 3a. AMP ^, L. ut -» *• 2< IL Ul O OU U < z 3 Q a 3 a u MU — rr Oz 50 u 0<L St s:s HS BORING NO., SOIL TEST DESCRIPTION SP 5- SC 10' 15- 20- 25- 30- 35- 40-4 X BEDROCK: li^t tan nedium SAND, moist, loose. At 2.1, groundvater encountered. T.ight: tan, mediun SAND with clay, very moist, sli^tly dense. light brown sandy CLAY, very moist, slightly dense. Total Depth - 10' Groundwater encountered at 2,1' JO a no,: 1.172.1 LOG OF BORING ificuatu B7 AMERICAN ENGINEERING LABORATORIES DATE ftn«tPauFn- 5/30/89 LOGGED HV m GHQIIMO Fl PK/ATinW 69.52 METHOD OF DfllLLING:_U^;SrMg_ lOGATinM. Sta. 48 + 50 o Q Ui o U u w ICAI o u. .* 3a. AMP u. Ul Ui o ^< (L 0 aut u < z 3 a 3 ca O -g——- mt §S Mui — fm Oz so u Oa. s:s ss BORING NO. DESCRIPTION SOIL TEST 5- 10- 15- 20- 25- 30- 35- 40-^ SP SC SC BE[HXK: light yellow brom mediini SAND, moist, loose. light yellow brown SAND with clay, wet, slightly dense. Yellow green fine clayey SAND, moist medium dense. Total Depth - 10 No groundwater encountered. joa NO.: 1.172,1 LOG OF BORING AMERICAN ENGINEERING LABORATORIES 5/30/89 __ K^ETHOD OF DRILLING:.'^" ^ OATE CQSERVED:. LOGGED BV ^ .GROUND ELEVATION:. 69.20 LOCATION:. Sta. 48 + 40 9 a u 9 o u ICAI o OC ..^ 3a. AMP U. Ul Ui -* Ul o OM -i < 3 3 m^ a 3 a o MU —• r— Oz so u Oa. 5:s HS BORING NO., SOIL TEST DESCRIPTION 5- 10- 15- 20- 25- 30 35 40-1 SP sc BEIHXX: U^t tan to white mediun SAND, moist, loose. light yellow brown medium SAND with clay, dry to moist, medium dense. Groundvater ^countered at 9.5' Total Depth - ICf Groundwater encountered at 9.5' JO a no.: 1-172.1 LOG OF BORING iflCuAti: 09 AMERICAN ENGINEERING LABORATORIES . 4" Beaver Rig DATE OBSERVED: METHOD OF DRILLING: LOGGED HV GB fiRnimn PI C\/ATIQM' 69.06 LQCATIQN- Sta. 49 + 10 (L U O -0- < o U) < mi o o o ik Ul Jr o cc ^ 30. Ui .J (L Ul 3 O mt MU —' ^ Oz so u Oa. ts HS BORING NO., 10 SOIL TEST DESCRIPTION 5- 10- 15- 20- 25-1 a 30- 35- 40-4 BETO3C: light brown sandy CLAY, dry, very deise. Total Depth 1' No groundwater encountered. JO a no.: 1-172,1 LOG OF SORING If (CURE: BIO 1 1 J J Palomar airport road seepage investigation stations 43+00 > 46+00 Job no.il7Z1 Date: June 1989 I I Plate 1 It NOSCALE Ss Cist clSs E Sandstone Claystone Clayey sandstone lOW Geologic contact showing dip, dashed where burled and dotted where inferred ^ Approximate limits of investigation / Joint showing dip 10 Approximate location of ^ exploratory boring showing total BIO *^^P^^ u I i. r ll fl Palomar airport road seepage investigation stations 46+00 > 51+00 Job no.1172.1 Date: June 1989 Plate 2 FOR EXPLANATION SEE PUTH 1 A N /s NOSCAL£