HomeMy WebLinkAbout4505 Hughes Lane - Soils Report
4055 West Shaw Avenue, Suite 110 Fresno, CA 93722 (559) 271-9700 Fax (559) 275-0827 2321 Perseus Court Bakersfield, CA 93308 (661) 393-9711 Fax (661) 393-9710 11650
Mission Park Dr., Suite 108 Rancho Cucamonga, CA 91730 (909) 980-6455 Fax (909) 980-6435 3850 North Wilcox Road, Suite F Stockton, CA 95215 (209) 931-2226 Fax (209)
931-2227 SALEM Engineering Group, Inc. GeotechnicalEnvironmentalGeologyMaterialsTesting&InspectionForensicLaboratory
January 25, 2011 Job No. 2-210-0790 Mr. Ross Sweet Skarphol Associates 1801 Oak Street, Suite 111 Bakersfield, CA 93301 Subject: Soil Characteristics and Absorption Evaluation Proposed
Drainage Basin La Luz Del Mundo Church Hughes Lane (APN: 405-020-01) Bakersfield, California Dear Mr. Sweet: This report presents the results of our Soil Characteristics and Absorption
Evaluation for the site of the proposed drainage basin at La Luz Del Mundo Church on Hughes Hughes Lane in Bakersfield, California (see Figure 1). 1.0 PROJECT DESCRIPTION We understand
that design of the proposed development is currently underway; final details pertaining to the structures are unavailable. On a preliminary basis, it is understood that the drainage
basin will be designed as follows Required Volume: 1.308 acre feet Provided Volume: 1.541 acre feet Top Elevation: 373.0 feet Bottom Elevation: 363.0 feet High Water Elevation:
367.5 feet 2.0 SITE LOCATION AND DESCRIPTION The site is located on the northeast corner of State Highway 99 and Southern Pacific Railroad in Bakersfield, California (see Figure 1).
The site has an Assessor’s Parcel Number (APN) of 405-020-01. The site is relatively level with no major changes in grade.
January25,2011 –2– 22100790 3.0 PURPOSE AND SCOPE The purpose of this investigation is to evaluate the subsurface conditions encountered during field exploration
and to evaluate the absorption characteristics of the soil within the project site, suitability of the site to support the proposed basin. The scope of our investigation includes a program
of field exploration, permeability testing, engineering analysis and preparation of a final report. 4.0 FIELD EXPLORATION Our field exploration consisted of site surface reconnaissance
and subsurface exploration. The exploratory tests boring (P-1 and P-2) were drilled on January 15, 2011 within the proposed basin area at the approximate locations shown on Figure 1,
Site Plan. The test borings were advanced with a 6½-inch diameter auger rotated by a truck-mounted CME-45 drill rig. The test borings were extended to depths ranging from 15 to 32 feet
below the existing grade. The materials encountered in the test borings were visually classified in the field, and logs were recorded by a Professional Engineer at that time. Visual
classification of the materials encountered in the test borings was generally made in accordance with the Unified Soil Classification System (ASTM D2487). A soil classification chart
and key to sampling is presented on the Unified Soil Classification Chart, in Appendix "A." The logs of the test borings tests are presented in Appendix "A." Subsurface soil samples
were obtained by driving a Modified California sampler or a Standard Penetration Test (SPT) sampler. Penetration resistance blow counts were obtained by dropping a 140-pound hammer through
a 30-inch free fall to drive the sampler to a maximum depth of 18 inches. The number of blows required to drive the last 12 inches is recorded as Penetration Resistance (blows/foot)
on the logs of borings. Soil samples were obtained from the test borings at the depths shown on the logs of borings. The samples were recovered and capped at both ends to preserve the
samples at their natural moisture content. At the completion of drilling and sampling, the test borings were backfilled with drill cuttings. 5.0 LABORATORY TESTING Laboratory tests were
performed on selected soil samples to evaluate their physical characteristics and engineering properties. The laboratory testing program was formulated with emphasis on the evaluation
of natural moisture, density, and permeability of the materials encountered. Details of the laboratory test program and the results of laboratory test are summarized in Appendix "A."
This information, along with the field observations, was used to prepare the final boring logs in Appendix "A." 6.0 SOIL AND GROUNDWATER CONDITIONS Based on our findings, the subsurface
conditions encountered appear typical of those found in the geologic region of the site. In general, the subsurface soil predominately consisted of medium dense silty sand (SM), sand
(SP) and silt (ML). These soils extended to the termination depth of our borings. The soils were classified in in the field during the drilling and sampling operations. The stratification
lines were approximated by the field engineer on the basis of observations made at the time of drilling. The actual boundaries between different soil types may be gradual and soil conditions
may vary.
January25,2011 –3– 22100790 For a more detailed description of the materials encountered, the Boring Logs (Figures A-1 and A-2 in Appendix "A") should be
consulted. The Boring Logs include the soil type, color, moisture content, dry density, and the applicable Unified Soil Classification System symbol. The locations of the test borings
were determined by measuring from features shown on the Site Plan, provided to us. Hence, accuracy can be implied only to the degree that this method warrants. Test boring locations
were checked for the presence of groundwater during and immediately following the drilling operations. Free groundwater was not encountered. It should be recognized that water table
elevations may fluctuate with time, being dependent upon seasonal precipitation, irrigation, land use, and climatic conditions as well as other factors. Therefore, water level observations
at the time of the field investigation may vary from those encountered during the construction phase of the project. The evaluation of such factors is beyond the scope of this report.
7.0 CONCLUSIONS AND RECOMMENDATIONS Based upon the data collected during this investigation, and from a geotechnical engineering standpoint, it is our opinion that the site is suitable
for the proposed drainage basin development. The proposed basin may be constructed provided that the recommendations presented herein are incorporated in the design and construction
of the project. 7.1 Permeability Testing Laboratory tests were performed on selected soil samples to evaluate their physical characteristics and engineering properties. The laboratory-testing
program was formulated with emphasis on the evaluation of gradation and permeability. Details of the laboratory test program and the results of laboratory test are summarized in Appendix
"A." Four permeability tests were performed on undisturbed soil samples collected from a depth of 10 to 32 feet below existing site grade. The permeability tests were performed in accordance
with ASTM Test Method D2434. The test results are as follows: TABLE 1 SUMMARY OF PERMEABILITY TEST RESULTS Test No. Depth (feet) Coefficient of Permeability (cm/second) Soil Type P-1
20 2.0 x 10-2 Sand (SP) P-1 32 2.2 x 10-2 Sand (SP) P-2 10 1.8 x 10-7 Silty Sand (SM) P-2 15 1.4 x 10-5 Silty Sand (SM) The soils encountered within the site predominately consisted
of alternating layers of medium dense silty sand, sand and silt. As shown on the table above, the site soils had low to high absorption characteristics with a coefficient of permeability
ranging from 2.2 x 10-2 to 1.8 x 10-7 centimeter per second (cm/sec). The estimated soil absorption factors presented in this report are based on clear water and a factor of safety should
be incorporated into the design of the reservoirs to compensate for soil clogging from water impurities.
January25,2011 –4– 22100790 7.3 Drainage Basin Design It is recommended that the proposed basins be constructed into the sandy soils encountered. It is
further recommended that a representative of our firm be present during the installation of the basins to determine soil conditions below the bottom of the basins. The basins should
be designed to drain in 7 days using the absorption capacity (Q) shown in the table below. SUMMARY OF ABSORPTION CAPACITY IN THE BASIN Test No. Depth (feet) Absorption (gallons/ft2/day)
for water head D (in feet) P-1 20 430D P-1 32 473D P-2 10 0.004D P-2 15 0.301D The absorption rates will deteriorate over time due to the soil conditions and a factor of safety (FS)
of 3 is recommended for design of the basin. In addition, periodic maintenance consisting of clearing the bottom of the drainage basin of clogged soils should be expected. The drainage
basins may become impermeable if the filter is clogged or the soil is compacted. The absorption rate may become slower if the surrounding soil is wet or saturated due to prolonged rainfalls.
The owner or civil engineer may elect to use a lower factor of safety for the design; however, more frequent maintenance consisting of clearing the bottom of the drainage basins of clogged
soils will be expected. Additional testing may be conducted at bottom of the drainage basin during construction to determine the absorption rate. Darcy Columns Based on the results of
our permeability testing, the upper site soils at P-2 location appear to have relatively low absorption characteristics. Soils encountered below 15 feet at P-1 location appear to have
more favorable absorption characteristics. In lieu of excavating the proposed basin to 20 feet below grade in order to utilize the soils with favorable absorption characteristics, Darcy
Columns “drains” maybe constructed at the site. SALEM recommends that the drains be at least 24 inches in diameter, spaced 12 feet center to center, and extend to a minimum depth of
25 feet below existing grade. The drains should be backfilled with a granular aggregate base material conforming to ASTM D-2940-03 with at least 95 percent passing a 1½-inch sieve and
not more than 8% passing a No. 200 sieve. It is further recommended that a representative of our firm be present during the installation of the system to confirm soil conditions below
the bottom of the proposed system. 8.0 CHANGED CONDITIONS The scope of our services did not include a groundwater study and was limited to the performance of permeability testing and
the submitted of the data only. The analyses and recommendations submitted in this report are based upon the data obtained from the two test borings drilled at the approximate locations
shown on the Site Plan, Figure 1. The report does not reflect variations which may occur between borings. The nature and extent of such variations may not become evident until construction
is initiated. If variations then appear, a re-evaluation of the recommendations of this report will be necessary after performing on-site observations during the excavation period and
noting the characteristics of such variations.
January25,2011 –5– 22100790 The findings and recommendations presented in this report are valid as of the present and for the proposed construction. If
site conditions change due to natural processes or human intervention on the property or adjacent to the site, or changes occur in the nature or design of the project, or if there is
a substantial time lapse between the submission of this report and the start of the work at the site, the conclusions and recommendations contained in our report will not be considered
valid unless the changes are reviewed by SALEM and the conclusions of our report are modified or verified in writing. The validity of the recommendations contained in this report is
also dependent upon an adequate testing and observations program during the construction phase. Our firm assumes no responsibility for construction compliance with the design concepts
or recommendations unless we have been retained to perform the on-site testing and review during construction. SALEM has prepared this report for the exclusive use of the owner and project
design consultants. The report has been prepared in accordance with generally accepted geotechnical engineering practices in the area. No other warranties, either expressed or implied,
are made as to the professional advice provided under the terms of our agreement and included in this report. We appreciate the opportunity to submit this proposal for your consideration
and look forward to working with you on this project. Should you have questions regarding this proposal, please contact the undersigned at (661) 393-9711. Respectfully submitted, SALEM
Engineering Group, Inc. Greg Walker Regional Manager R. Sammy Salem, MS, PE, GE, REA Principal Engineer RCE 52762 /RGE 2549 Clarence Jiang, GE Senior Geotechnical Engineer RGE 2477 Attachments:
Site Plan, Figure 1 Appendix A
APPROVED BY: SCALE: DATE: DRAWN BY: PROJECT NO. FIGURE NO. LEGEND: Test Location SITE PLAN P-1 NOT TO SCALE RSS 01/05/2011 RSS 2-210-0790 1 N SALEM Engineering Group, Inc. DRAINAGE BASIN
EVALUATION PROPOSED LA LUZ DEL MUNDO CHURCH HUGHES LANE (APN: 405-020-01) BAKERSFIELD, CALIFORNIA (All Locations Approximate) P-1 P-2
APPENDIX "A"
Letter Symbol GW GP GM GC SW SP SM SC ML CL OL MH CH OH PT Organic clays of medium to high plasticity. Peat, muck, and other highly organic soils. Well-graded sands and gravelly sands,
little or no fines. Poorly-graded sands and gravelly sands, little or no fines. Silty sands, sand-silt mixtures Inorganic clays of low to medium plasticity, gravelly clays, sandy clays,
silty clays, lean clays. Unified Soil Classification System Clayey sands, sandy-clay mixtures. Organic clays of medium to high plasticity. Inorganic silts, micaceous or diatomaceous
fines sands or silts, elastic silts. Description Silts and Clays Liquid Limit greater than 50% Gravels With Fines Clean Sands Major Divisions Clean Gravels Sands More than ½ passing
through the No. 200 sieve Inorganic silts, very fine sands, rock flour, silty or clayey fine sands. Gravels More than ½ coarse fraction retained on the No. 4 sieve Inorganic clays of
high plasticity, fat clays. Consistency Classification Highly Organic Soils Coarse-grained Soils More than ½ retained on the No. 200 Sieve Coarse-grained Soils More than ½ passing through
the No. 200 Sieve Sands With Fines Silts and Clays Liquid Limit less than 50% Well-graded gravels and gravel-sand mixtures, little or no fines. Poorly-graded gravels and gravel-sand
mixtures, little or no fines. Silty gravels, gravel-sand-silt mixtures. Clayey gravels, gravel-sand-clay mixtures. Granular Soils Cohesive Soils Description -Blows Per Foot (Corrected)
Description -Blows Per Foot (Corrected) MCS <5 5 ¯ 15 16 ¯ 40 41 ¯ 65 >65 SPT <4 4 ¯ 10 11 ¯ 30 31 ¯ 50 >50 Very loose Loose Medium dense Dense Very dense Very soft Soft Firm Stiff Very
Stiff Hard MCS <3 3 ¯ 5 6 ¯ 10 11 ¯ 20 21 ¯ 40 >40 SPT <2 2 ¯ 4 5 ¯ 8 9 ¯ 15 16 ¯ 30 >30 MCS = Modified California Sampler SPT = Standard Penetration Test Sampler
Project: Project No: Client: Location: Figure No.: Logged By: Depth to Water> Initial: At Completion: Equipment: Drill Method: Drill Date: Hole Size: Driller: Sheet: 1 of 2 SALEM EngineeringGroup
,Inc. SUBSURFACE PROFILE SAMPLE Depth (ft) 05 10 15 20 25 Symbol Description Dry Density (pcf) Moisture Content (%) Sample Type Penetration Blow Count Penetration Test Water Level
Proposed La Luz Del Mundo Church 2-210-0790 Skarphol Associates Hughes Lane & Blue Mountain Way, Bakersfield, CA A-1 M.A. None None Ground Surface Silty Sand (SM) Medium dense; moist;
brown; medium to fine-grained; trace of mica; drills easily. Sand (SP) Medium dense; dry to moist; brown; medium to fine-grained; trace of mica; drills easily. Grades with silt at 5
feet. Grades off-white with black mottling; fine-grained. 86.8 2.5 MCS 26 20 60 100 CME-45 Hollow Stem Auger 01.05.11 6½ inch SALEM P-1
Project: Project No: Client: Location: Figure No.: Logged By: Depth to Water> Initial: At Completion: Equipment: Drill Method: Drill Date: Hole Size: Driller: Sheet: 2 of 2 SALEM EngineeringGroup
,Inc. SUBSURFACE PROFILE SAMPLE Depth (ft) 30 35 40 45 50 Symbol Description Dry Density (pcf) Moisture Content (%) Sample Type Penetration Blow Count Penetration Test Water Level
Proposed La Luz Del Mundo Church 2-210-0790 Skarphol Associates Hughes Lane & Blue Mountain Way, Bakersfield, CA A-1 M.A. None None End of Borehole N/A N/A MCS 46 20 60 100 CME-45 Hollow
Stem Auger 01.05.11 6½ inch SALEM
Project: Project No: Client: Location: Figure No.: Logged By: Depth to Water> Initial: At Completion: Equipment: Drill Method: Drill Date: Hole Size: Driller: Sheet: 1 of 1 SALEM EngineeringGroup
,Inc. SUBSURFACE PROFILE SAMPLE Depth (ft) 05 10 15 20 25 Symbol Description Dry Density (pcf) Moisture Content (%) Sample Type Penetration Blow Count Penetration Test Water Level
Proposed La Luz Del Mundo Church 2-210-0790 Skarphol Associates Hughes Lane & Blue Mountain Way, Bakersfield, CA A-2 M.A. None None Ground Surface Silty Sand (SM) Medium dense; moist;
brown; medium to fine-grained; drills easily. Silt (ML) Medium dense; moist; brown; medium to fine-grained; drills easily. Silty Sand (SM) Dense; moist; tan; medium to finegrained; trace
of mica; drills firmly. End of Borehole 98.8 99.7 6.2 6.2 MCS MCS 36 30 20 60 100 CME-45 Hollow Stem Auger 01.05.11 6½ inch SALEM P-2
Soil Permeability Constant Head ASTM D-2434 /Cal 220 Project Number :2-210-0790 Project Name :La Luz Del Mundo Church Date :1/12/2011 Sample Number :P-1 Sample Location :P-1 @20' Soil
Classification :SP Max Dry Density --lb/cu.ft Relative Density --Max. Particle Size 3/4" Optimum Moisture --% %Over Optimum --% Passing 3/8" --Sample Dry Density --lb/cu.ft Void Ratio
--% Passing # 10 --Sample Moisture --% Sample Length, cm 11.2 Sample Diameter 6.2 Sample Compaction --% Sample Area sq.cm 29.7 25.1 Comp. Procedure Type of Permeant water Start Finish
Head Flow Test Time Time (cm) Q (cm3) 1 3:00:00 15:01:00 105.5 427.00 2 15:05:00 15:06:00 54.8 271.00 3 15:08:00 15:09:00 54.8 222.00 4 15:10:00 15:11:00 132.9 533.00 5 15:12:00 15:13:00
54.8 246.00 6 Time Head Flow K k20 Test sec (cm) Q (cm3) cm/sec cm/sec 1 43260 105.5 427.0 3.53E-05 3.134E-05 Permeability 2 60 54.8 271.0 3.10E-02 2.758E-02 2.0E-02 cm/sec 3 60 54.8
222.0 2.54E-02 2.259E-02 2.8E+01 in/hr. 4 60 132.9 533.0 2.52E-02 2.238E-02 5.5E+01 ft/day 5 60 54.8 54.8 246.0 2.82E-02 2.503E-02 20129.36 ft/year 6 Sliding Weight Temperature SALEM
Engineering Group, Inc.
Soil Permeability Constant Head ASTM D-2434 /Cal 220 Project Number :2-210-0790 Project Name :La Luz Del Mundo Church Date :1/12/2011 Sample Number :P-2 Sample Location :P-1 @32' Soil
Classification :SP Max Dry Density --lb/cu.ft Relative Density --Max. Particle Size 3/4" Optimum Moisture --% %Over Optimum --% Passing 3/8" --Sample Dry Density --lb/cu.ft Void Ratio
--% Passing # 10 --Sample Moisture --% Sample Length, cm 10.7 Sample Diameter 6.2 Sample Compaction --% Sample Area sq.cm 29.7 25.1 Comp. Procedure Type of Permeant water Start Finish
Head Flow Test Time Time (cm) Q (cm3) 1 14:00:00 14:01:00 54.8 183.00 2 14:05:00 14:06:00 54.8 212.00 3 14:09:00 14:10:00 54.8 280.00 4 14:12:00 14:13:00 54.8 246.00 56 Time Head Flow
K k20 Test sec (cm) Q (cm3) cm/sec cm/sec 1 60 54.8 183.0 2.00E-02 1.778E-02 Permeability 2 60 54.8 212.0 2.32E-02 2.059E-02 2.2E-02 cm/sec 3 60 54.8 280.0 3.06E-02 2.720E-02 3.2E+01
in/hr. 4 60 54.8 246.0 2.69E-02 2.390E-02 6.3E+01 ft/day 5 23059.64 ft/year 6 Sliding Weight Temperature SALEM Engineering Group, Inc.
Soil Permeability Constant Head ASTM D-2434 /Cal 220 Project Number :2-210-0790 Project Name :La Luz Del Mundo Church Date :1/10/2011 Sample Number :P-3 Sample Location :P-2 @10' Soil
Classification :SM Max Dry Density --lb/cu.ft Relative Density --Max. Particle Size 3/4" Optimum Moisture --% %Over Optimum --% Passing 3/8" --Sample Dry Density --lb/cu.ft Void Ratio
--% Passing # 10 --Sample Moisture --% Sample Length, cm 14.0 Sample Diameter 6.2 Sample Compaction --% Sample Area sq.cm 29.7 25.1 Comp. Procedure Type of Permeant water Start Finish
Head Flow Test Time Time (cm) Q (cm3) 1 9:57:00 11:12:00 527.3 1.30 2 11:20:00 14:05:00 439.4 2.00 3 14:08:00 15:55:00 681.9 1.30 4 16:00:00 17:30:00 660.8 1.30 5 8:22:00 16:11:00 615.1
7.50 6 Time Head Flow K k20 Test sec (cm) Q (cm3) cm/sec cm/sec 1 4500 527.3 1.3 2.58E-07 2.293E-07 Permeability 2 9900 439.4 2.0 2.16E-07 1.924E-07 1.8E-07 cm/sec 3 6420 681.9 1.3 1.40E-07
1.243E-07 2.5E-04 in/hr. 4 5400 660.8 1.3 1.72E-07 1.525E-07 5.0E-04 ft/day 5 28140 615.1 7.5 2.04E-07 1.813E-07 0.18 ft/year 6 Sliding Weight Temperature SALEM Engineering Group, Inc.
Soil Permeability Constant Head ASTM D-2434 /Cal 220 Project Number :2-210-0790 Project Name :La Luz Del Mundo Church Date :1/10/2011 Sample Number :P-4 Sample Location :P-2 @15' Soil
Classification :SM Max Dry Density --lb/cu.ft Relative Density --Max. Particle Size 3/4" Optimum Moisture --% %Over Optimum --% Passing 3/8" --Sample Dry Density --lb/cu.ft Void Ratio
--% Passing # 10 --Sample Moisture --% Sample Length, cm 10.9 Sample Diameter 6.2 Sample Compaction --% Sample Area sq.cm 29.7 25.1 Comp. Procedure Type of Permeant water Start Finish
Head Flow Test Time Time (cm) Q (cm3) 1 11:32:00 11:36:00 681.9 7.00 2 11:38:00 11:42:00 639.7 6.70 3 11:44:00 11:48:00 692.5 7.40 4 11:50:00 11:54:00 681.9 7.20 56 Time Head Flow K
k20 Test sec (cm) Q (cm3) cm/sec cm/sec 1 240 681.9 7.0 1.57E-05 1.400E-05 Permeability 2 240 639.7 6.7 1.61E-05 1.428E-05 1.4E-05 cm/sec 3 240 692.5 7.4 1.64E-05 1.457E-05 2.0E-02 in/hr.
4 240 681.9 7.2 1.62E-05 1.439E-05 4.0E-02 ft/day 5 14.75 ft/year 6 Sliding Weight Temperature SALEM SALEM Engineering Group, Inc.