Loading...
HomeMy WebLinkAboutTract Map 23561 Lot 11 Geotechnical Reports Sanborn " I • I 1 I � 1 1 ' RIO 0-4 f � ,ty / fir' Or 61 L• �w)Ir � .c_. / « � i/� ter, r� b'/� r • G "'1F'1.�,y�/� �� # . 1 J f '0 / t 4 `.. i... !� u �t Sri y .• Tl, 38 Q I G it ;g tA Ca ftc n/W,Envbo ~tsl and Mate,/ds T"dng Conwlbnb BETTER PEOPLE•BETTER SERVICE•BETTER RESULTS May 15,2015 Project No. 15802-12A Paul and Andy Laubach PROVIDENCE CAPITAL GROUP,LLC 183 Calle Magdalena,Suite 100 Encinitas,CA 92024 Subject: Interpretive Report for Infiltration System Design, Proposed Commercial Development, Assessor's Parcel Number 910-272-011, Located at 41427 Sanborn Avenue, City of Temecula, Riverside County,California Earth-Strata, Inc. is pleased to present this interpretive report for the proposed commercial development, located at 41427 Sanborn Avenue, in the City of Temecula, Riverside County, California. The purpose of our study was to determine the infiltration rates and physical characteristics of the subsurface earth materials within the proposed development. We have provided guidelines for the design of onsite bio swale retention systems,where applicable. This study is intended to provide onsite infiltration rates for the earth materials at the approximate depth near the proposed retention basins. PROPERTY DESCRIPTION The subject property is located at 41427 Sanborn Avenue in the City of Temecula, Riverside County, California (see Figure 1). The subject property consists of an undeveloped parcel of land with relatively flat terrain. The subject property is underlain by compacted fill and alluvium. PROPOSED CONSTRUCTION Based on information provided by you, the proposed development will consists of a parking lot with interior driveways, utilities and on-site retention basins. SUBSURFACE EXPLORATION AND INFILTRATION TESTING SUBSURFACE EXPLORATION Subsurface exploration of the subject site consisted of 3 exploratory excavations to a depth of 11 Y2 feet, conducted on May 12, 2015. The exploratory holes were excavated to evaluate insitu permeability rates. The approximate location of the exploratory excavations are shown on the attached Infiltration Location Map, Plate 1. EARTH MATERIALS A general description of the earth materials observed on site is provided below. • Artificial Fill Undocumented (map symbol AO: Undocumented artificial fill materials were encountered throughout the site within the upper 5 feet during exploration. These materials are typically locally derived from the native materials and consist generally of yellowish brown clayey sand. These materials are generally inconsistent,well consolidated fills. • Quaternary Young Fan Deposits (tromp symbol Oyfl: Quaternary old fan deposits were encountered to a maximum depth explored. These alluvial deposits consist predominately of gray brown, fine to coarse grained sand interlayered with sandy silt. These deposits were generally noted to be in a moist, medium dense. GROUNDWATER Groundwater was not observed within the exploratory excavations. INFILTRATION TESTING The continuous presoak test method was utilized to perform a total of four (4) infiltration tests on April 25, 2015 to evaluate near surface infiltration rates in order to estimate the amount of storm water runoff that can percolate into the onsite bio Swale retention basins. The infiltration tests were performed in general accordance with the requirements of insitu infiltration testing. The infiltration tests were performed within 3 inch perforated pipes, 3 to 4 feet deep. The locations of the infiltration test holes are indicated on the attached Infiltration Location Map, Plate 1. The infiltration test holes were located by property boundary measurement on the site plan and by using geographic features. For the continuous presoak testing method,the pipe was filled with water and allowed to stand. After the presoak,testing was performed by adjusting the water level to near the top of the pipe. The drop in water level was measured from a fixed initial reference point for more reliable readings, with measurements having an accuracy of 1/8-inch. After each measurement, the water level was brought up to the original test level. Infiltration test data recorded in the field is summarized in the following table and is included within Appendix A. INFILTRATION TEST SUMMARY TEST FILTRATION INFILTRATION NUMBER HOLE DEPTH (ft.) RATE (mpi) P-1 3.5 60 Silty SAND P-2 3.5 60 Silty SAND P-3 4 48 Silty SAND P-4 3 60 Silty SAND The infiltration test rates ranged from 48 to 60 minutes per inch (mpi). CONCLUSIONS AND RECOMMENDATIONS Based on the data presented in this report and the recommendations set forth herein, it is the opinion of Earth- Strata that the retention basin can be designed for a infiltration rate of 60 mpi. EARTH-STIRLA A, Inc. 2 May 15, 2015 Project Number 15802-12A The following equation was used in order to convert the infiltration rates to infiltration rates. I, _ AH (601 r At (r+ 2Havg) The infiltration rate of 60 mpi is to be used for the design. This rate is used in the conversion equation utilizing the Porchet Method to obtain the infiltration rate of 0.1 inch/hour.The infiltration rate is below county standards. See Attached Sheets. GRADING PLAN REVIEW AND CONSTRUCTION SERVICES This report has been prepared for the exclusive use of Providence Capital Group, LLC and their authorized representative. It likely does not contain sufficient information for other parties or other uses. Earth-Strata should be engaged to review the final design plans and specifications prior to construction. This is to verify that the recommendations contained in this report have been properly incorporated into the project plans and specifications. Should Earth-Strata not be accorded the opportunity to review the project plans and specifications, we are not responsibility for misinterpretation of our recommendations. Earth-Strata should be retained to provide observations during construction to validate this report. In order to allow for design changes in the event that the subsurface conditions differ from those anticipated prior to construction. Earth-Strata should review any changes in the project and modify and approve in writing the conclusions and recommendations of this report This report and the drawings contained within are intended for design input purposes only and are not intended to act as construction drawings or specifications. In the event that conditions encountered during grading or construction operations appear to be different than those indicated in this report, this office should be notified immediately,as revisions may be required. REPORT LIMITATIONS Our services were performed using the degree of care and skill ordinarily exercised; under similar circumstances, by reputable soils engineers and geologists, practicing at the time and location this report was prepared. No other warranty,expressed or implied, is made as to the conclusions and professional advice included in this report. Earth materials vary in type, strength, and other geotechnical properties between points of observation and exploration. Groundwater and moisture conditions can also vary due to natural processes or the works of man on this or adjacent properties. As a result, we do not and cannot have complete knowledge of the subsurface conditions beneath the subject property. No practical study can completely eliminate uncertainty with regard to the anticipated geotechnical conditions in connection with a subject property. The conclusions and recommendations within this report are based upon the findings at the points of observation and are subject to confirmation by Earth-Strata during construction. This report is considered valid for a period of one year from the time the report was issued. EARTH-STRATA, Inc. 3 May 15, 2015 Project Number 15802-12A This report was prepared with the understanding that it is the responsibility of the owner or their representative, to ensure that the conclusions and recommendations contained herein are brought to the attention of the other project consultants and are incorporated into the plans and specifications. The owners'contractor should properly implement the conclusions and recommendations during grading and construction, and notify the owner if they consider any of the recommendations presented herein to be unsafe or unsuitable. Respectfully submitted, EARTH-STRATA, INC. QQp. . /s!vo. 692 p i! tJ• W Exp T 4Stepen . Poole, PE 40219 *~J' ^' t President �EL1N1` Principal Engineer sl��FOF gA`�FpQ6' SMP/ca Distribution: (4)Addressee Attachments: Figure 1 -Vicinity Map(Rear of Text) Appendix A- Infiltration Test Sheets(Rear of Text) Plate 1 -Infiltration Location Map(Rear of Text) EARTFI-STRATA. Irec 4 May 15, 2015 Project Number 15802-12A FIGURE 1 VICINITY MAP Ja 1r 1'fi V C f f � FF r by � SVMf11.AD,• a 9 It bg 1Ire L I �t fell( �h�w eP°d } n.. . V J• £ ^3 --� - 1A d. ?° i r 4� dye no"'awro a q� o°~w '_ ! r, W ape`s✓ \s ems" i,s _r s off ' ,� .io, MU M1a Ma15Pm0 �° t'I I c y j Y ni cr,d i S. a' d I5802-f0A 5onborn Avenue : Approximate Site Location , �ypP,,g �\ 61, 1 ¢ oeL -. a ,a Id- `G 2007 DeLorme (www delorme com) Topo USAW SANBORN AVENUE 15802-10A SEE BAR SCALE VICINITY MAP MAY 2015 (FIGURE 1 1 - APPENDIX A INFILTRATION TEST SHEETS Job No.: 15802-12A Tested By: TI "It"is the tested infiltration rate. Job Name: providence II Time interval, Ni Initial Depth to Water,D, Test Hole Number: P-1 Test Hole Diameter(inches): 8 Final Depth to Water,D. Total Depth of Test Hole,D 1 Soil Classification: GP Date Excavated: 4/24/2015 2Test Hole Radius,r Test Hole Depth(ft): 3.5 Date Tested: 4/25/2015 The conversion equation Is used: Time Interval of Presoak "Havg"is the average head height over the time interval. Date/Time 0 Start 4/25/1511:00 Amount of Water Used/Comments It = , AN 60r Stop 4/25/1517:00 0 At(r+2Havg) Final Percolate Total total Time Inftlal Water Water water nRafe Depth of 77.1 Initial Final Depthof Roduisof all 60 glut ELAPSED 71me Interval Level Dlap (min.J Level(Irrchesl Level percoloHo interval Water Water test Xak Pere llok (nrNap)J TAf M nHole 4l He HI Di r dH MAvg It Ahk 11:00 30 13 15 2.00 15 42.00 30.00 29.00 27.00 42.00 4.00 2.00 28.00 0.27 30.D0 11:30 11:30 30 15 17 2.00 15 42.00 30.00 27.00 25.00 42.00 4.00 2.00 26.00 0.29 60.00 12:00 12:00 30 17 18 1.00 30 42.00 30.00 25.00 24.00 42.00 4.00 1.00 24.50 0.15 90.00 12:30 12:30 30 18 19 E0.5060 42.00 30.00 24.00 23.00 42.00 4.00 1.00 23.50 0.16 120.00 1300 13: 00 30 19 19.5 42.00 30.00 23.00 22.50 42.00 4.00 0.50 22.75 0.08 150.00 1330 13:30 30 19.5 20 42.00 30.00 22.50 22.00 42.00 4.00 0.50 22.25 0.08 180.00 14:00 14:00 30 20 20.5 42.00 30.00 22.00 21.50 42.00 4.00 0.50 21.75 0.08 210.00 14:30 14:30 30 20.5 21 0.50 60 42.00 30.00 21.50 21.00 42.00 4.00 0.50 21.25 0.09 240.D0 15:00 15:00 30 21 21.5 0.50 60 42.00 30.00 21.00 20.50 42.00 4.00 0.50 20.75 0.09 270.00 15:30 15:30 30 21.5 22 0.50 60 42.00 30.00 20.50 20.00 42.00 4.00 0.50 20.25 0.D9 300.00 16:00 16:00 30 22 22.5 0.50 60 42.00 30.00 20.00 19.50 42.00 4.00 0.50 19.75 0.09 330.00 16:30 16:30 30 22.5 23 0.50 60 42.00 30.00 19.50 19.00 42.00 4.00 0.50 19.25 0.09 360.00 17:00 Job No.: 15802-12A Tested By: TI "It"is the tested infiltration rate. Job Name: Providence II Time interval, V Initial Depth to Water,IY Test Hole Number: P-2 Test Hole Diameter(inches): a Final Depth to Water,1) Total Depth of Test Hole.D, Soil Classification: GP Date Excavated: 4/24/2015 Jest Hole Radius,r Test Hole Depth(it): 3.5 Date Tested: 4/25/2015 The conversion equation is used: Time interval of Presoak "Havg"is the average head height over the time interval. Date/Time 0 Start 4/25/1511:01 Amount of Water Used/Comments It _ AH 60r Stop 11251201517:01:00 PN 0 At(r@Havg) Final percolatloI rota Time Initial Water Water Water n Nate Initial Final Depth of Raduks of AH 60 r)/fAt ELAPSED 'Time Interval InelOrop Water Wirter T Perc Hole (r�2HaW)) TIME _ Nr HI AN HAvq It 41 11:01 30 14 16 2.00 15 30.00 28.00 26.00 42.00 4.00 2M 27.00 0.28 3000 11:3111:31 30 16 18 2.00 15 30.DO 26.00 24.00 42.00 4.00 2.00 25.00 0.30 60.00 12:0112:01 30 18 19.5 1.50 20 30.00 24.00 22.50 42.00 4.00 1.50 23.25 0.24 90,00 12:31 12:31 30 19.5 21 1.50 20 42.00 30.00 22.50 21.00 42.00 4.00 1.50 21.75 0.25 120.00 13:03 13:01 30 21 21.5 0.50 60 42.00 30.00 21.00 20.50 42.00 4.00 0.50 20.75 0.09 150.00 13:31 13:31 30 21.5 22 0.50 60 42.00 30.00 20.50 20.00 42.00 4.00 0.50 20.25 0.09 180.00 14:01 14:01 30 22 22.5 0.50 60 42.00 30.00 20.00 19.50 42.00 4.D0 0.50 19.75 0.09 210.00 14:31 14:31 30 22.5 23 0.50 60 42.00 30.00 19.50 19.00 42.00 4.00 0.50 19.25 0.09 240.00 15:01 15:01 30 23 23.5 0.50 60 42.00 30.00 19.00 18.50 42.00 4.00 0.50 18.75 0.10 270.00 15:31 15:31 30 23.5 24 0.50 60 42.00 30.00 18.50 18.00 42.00 4.00 0.50 18.25 0.20 300.00 16:01 16:01 30 24 24.5 0.50 60 42.00 30.00 18.00 17.50 42.00 4.00 0.50 17.75 0.10 330.00 16:31 16:31 30 24.5 25 0.50 60 42.00 30.00 17.50 17.00 42.00 4.00 0.50 17.25 0.10 360.00 17:01 Job No.: 15802-12A Tested By: TI "It"is the tested infiltration rate. Job Name: Providence It Time interval, N1 Initial Depth to Water,I) Test Hole Number: P-3 Test Hole Diameter(inches): 8 Final Depth to Water,1) Total Depth of Test Hole,D i Soil Classification: GP Date Excavated: 4/24/2015 .Test Hole Radius,r Test Hole Depth(ft): 4 Date Tested: 4/25/2015 The conversion equation is used: Time Interval of Presoak "Havg"is the average head height over the time interval. Date/Time 0 Start 4/25/1511:02 Amount of Water Used/Comments It _ dH 60 r Stop 4/25/1517:02 0 6t(r+2Havg) Final Water Percalada Total Time Initial Water Water nRare Depths Time MINaI Fhwl Rodllb of , r//fdt EUGSEO Time Mrerval Level(Inchesl Level L4rv�ILllap in twat Water Water It IYrt Note, Il _ Inches) 0, r dN MAvg It 11:02 30 13.5 15.5 2.00 15 48.00 30.00 34.50 32.50 48.00 4.00 2.00 33.50 0.23 30.G0 11 32 1132 30 15.5 17.5 2.00 15 48.00 30.00 32.50 30.50 48DC 4.00 2.00 31.50 0.24 60.00 12:02 12:02 30 17.5 18.25 0.75 40 48.00 30.00 30.50 29.75 48.00 4.00 0.75 30.13 0.D9 90.00 12:32 12:32 30 18.25 19 0.75 40 48.00 30.00 29.75 29.00 48.00 4.00 0.75 29.38 0.10 120.00 13:02 13:02 30 19 20 1.00 30 48.00 30.00 29.00 28.00 48.00 4.00 1.00 28.50 0.13 150.00 13:32 13:32 30 20 21 1.00 30 48.00 30.00 28.00 27.00 48.00 4.00 1.00 27.50 0.14 180.00 14:02 14:02 30 21 22 1.00 30 48.00 30.00 27.D0 26.00 48.00 4.00 1.00 26.50 0.14 210.00 14:32 14:32 30 22 23 1.00 30 48.00 30.00 26.00 25.00 48.D0 4.00 1.00 25.50 0.15 240.00 15:02 15:02 30 23 24 1.00 30 48.00 30.00 25.00 24.00 48.00 4.00 1.00 24.50 0.15 270.00 15:32 15:32 30 24 25 1.00 30 48.00 30.00 24.00 23.00 48.00 4.00 1.00 23.50 0.16 300.00 16:02 16:02 30 25 26 1.00 30 48.00 30.00 23.00 22.00 48.00 4.00 1.00 22.50 0.16 330.00 16:32 16:32 30 26 27 1.00 30 48.00 30.00 22.00 21.00 48.00 4.00 1.00 21.50 0.17 360.00 1 ::02 Job No.: 15802-12A Tested By: Tl "It"is the tested Infiltration rate. Job Name: Providence II Time interval, %I Initial Depth to Water,1) Test Hole Number: P-4 Test Hole Diameter(inches): 8 Final Depth to Water,I h Total Depth of Test Hole,D i Soil Classification: GP Date Excavated: 4/24/2015 2Test Hole Radius,r Test Hole Depth(ft) 3 Date Tested: 4/25/2015 The conversion equation is used: rime Interval of Presoak "Havg"is the average head height over the time interval. Date/Time 0 Start 4/25/15 11:03 Amount of Water Used/Comments AH 60 r Stop 4/25/1517:03 0 It - At(r+2Havg) fin WoWateral Percolatb' Total Time Initial Water Water .Sole Thrrc lawal Final Depth./ 8adulsof AN W g1tat ELAPSEDTime Imerval Level(Inches) Level Level Drop (Mtn./Mch Teat Hole Perc Hok (02Navp)) TIME finches) (Inches) iMwMd&6 Dr I am N It At 11:03 30 30 13 3.00 30 36.00 30.00 26.00 23.00 36.00 4.00 3.00 24.50 0.45 30.00 21:33 11:33 30 13 15 2.00 15 36.00 30.00 23.00 21,00 36.00 4.00 2.00 22.DO 0.33 60.DO 12:03 12.03 30 15 16 1.00 30 36.00 MOD 21.00 20.00 36.00 4.00 1.DO 20.50 0.18 90.00 12:33 12:33 30 16 17 1.00 30 36.00 30.00 20.00 19.00 36.00 4.00 1.00 19.50 0.19 120.00 13:03 13:03 30 17 18 1.00 30 36.00 30.00 19.00 18.00 36.00 4.00 1.00 18.50 0.20 150.00 13:33 13:33 30 18 19 1.00 30 36.00 30.00 18.00 17.DO 36.00 4.00 1.00 17.50 0-21 180.00 14:03 14:03 30 19 19.5 0.50 60 36.00 30.00 17.00 16.50 36.00 4.00 0.50 16.75 0.11 210.00 14:33 14:33 30 19.5 20 0.50 60 36.00 30.00 16.50 16.00 36.00 4.00 0.50 16.25 0.11 240.00 15:03 15:03 30 20 20.5 0.50 60 36.00 30.00 16.00 15.50 36.00 4.00 0.50 25.75 0.11 270.00 15:33 15:33 30 20.5 21.5 1.00 30 36.00 30.00 15.50 14.50 36.00 4.00 1.00 15.00 0.24 300.00 16:03 16:03 30 20.5 22 1.50 20 36.00 30.00 15.50 14.00 36.00 4.00 1.50 14.75 0.36 330.00 16:33 16:33 30 22 22.5 0.50 60 36.00 30.00 14.00 13.50 36.00 4.00 0.50 13.75 0.13 360.00 17:03