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PZ - Geotech Report SITE Post Office Box 190537 - Boise, Idaho 83719 site.consulting.idaho@gmail.com - 208-440-6276 ZCON2SULTING, LLC Jim Merkle February 28, 2022 Northern Land Page 1 of 13 2150 North Canter Place File#22824-A Eagle, Idaho 83616 Re: Geotechnical Recommendation Report 3539 Locust Grove Road Meridian, Idaho Jim: As per your authorization, on February 9 2022, SITE personnel logged and sampled three test pits on the referenced property. The test pits were excavated in the fields west and east of the onsite manufactured home. Numerous out buildings are present on the property. All existing structures are to be demolished. During test pit excavation, soil samples were gathered and were submitted to our in- house soil laboratory for the testing required for soil classification. All soil classifications and test results are reported on the attached Test Pit Logs. The test pits were similar to each other. The surface soil includes brown, moist to wet, blocky, lean clay or silt that extends to 3-6' deep. At this depth, the top of the sand and gravel formation of the Whitney Terrace were contacted. The top of this gravel layer is weakly cemented. Free flowing sand and gravel with cobble are typically present two feet below gravel contact. Our test pits were extended to 10-15 feet deep. At this depth free flowing sand and gravel prevented deeper excavation. Groundwater was not encountered. Since the depth to groundwater was not determined, additional research has been provided. Numerous wells in the immediate vicinity of this project were found on the IDWR website. Two well logs were selected for inclusion in the Appendix. One is to the east and adjacent to the subject property and the second was just to the north. These three wells indicate that groundwater is 16- 23 feet deep. a Geotechnical services/soil Testing&Inspection Services SITE Post Office Box 190537 - Boise, Idaho 83719 C pp���+ site.consulting.idaho@gmail.com - 208-440-6276 ULTI Z/ONSULTI The following recommendations are based upon observed conditions and reported test results. • Stripping of organic material will require only minor excavation; 0-6" of grubbing can be anticipated to completely remove all organic materials. This is to be adjusted as needed in the field at the time of construction. Deeper excavation will be required along ditches and where large trees are present. • Demolition of all buildings is planned. Any crawlspace or basement section is to be backfilled with structural fill. • The surface soil encountered includes a layer of lean clay. While these soils are acceptable for support of foundations, fat clay is not. Inspection of foundation support subgrade is recommended to confirm that fat clays are not present. If encountered, over excavation will be required • For foundations founded atop the surface soil stratum, building code allowed bearing capacity of 1500 psf is appropriate for foundation design. • After grubbing and clearing, the building pads and any areas that will support future pavements, driveways, sidewalks, etc., should be scarified, moisture conditioned as needed, and recompacted to the requirement provided herein for structural fill. The subgrade below future pavements should be inspected at the time of construction to confirm stability and the absence of Fat Clay soil. • Imported structural fill used to repair over excavations or to elevate the building pad, support foundations or other concrete, and beneath future pavements should meet the Base or Subbase specifications of the ISPWC Specifications. • The cleared, grubbed, and approved subgrade and each lift of imported structural fill is to be compacted to a minimum of 95% of the maximum dry density as determined by ASTM D698, "Standard Proctor". This engineer can waive compaction testing after visual inspection of the subgrade. • Inplace testing to confirm proper compaction is required. Three tests per lift for every 5000 square feet or two tests per building pad per lift of fill are recommended. N bz a Geotechnica/Services/Soil Testing&Inspection Services SITE Post Office Box 190537 - Boise, Idaho 83719 ��** site.consulting.idaho@gmaii.com - 208-440-6276 ZCOLNSULTING.. LLL • Plastic soil may rut or deflect severely if wet when loaded with rubber tire equipment. Excessively wet or deflecting areas are to be over-excavated and repaired with structural fill. Inspection at the time of testing should confirm that subgrade and structural fill is firm and stable, and free of soft, excessively wet, or deflecting areas. • Compacted native soil and structural fill must pass both testing and inspection requirements. Deflecting and I or excessively wet soils fail regardless of compaction test results. • Unacceptable soils are to be removed to firm bearing or a maximum depth of two feet and replaced with structural fill. Over excavation of unacceptable soils must extend laterally outside foundations a distance equal to the depth of fill. • Based upon subgrade soils and anticipated traffic loads, it is recommended that the driveway meet ACHD's maximum section for residential streets as follows. Structural Layer Recommended Thickness HMA 2.5" Base Course 4.0" Subbase 12.0" If pavements are to be completed before the building structures, SITE recommends increasing the pavement thickness to 3.0" • Portland cement concrete is recommended for high traffic areas and areas of special loading such as dumpster storage and motorcycle parking. • All site concrete shall be placed atop a minimum of 6" of properly compacted subbase atop an inspected and approved subgrade. Concrete thickness to meet ISPWC requirements for sidewalks. • HMA, Portland cement concrete, base, and subbase used in pavement construction are to meet the materials quality and placement requirements of ISPWC. M aA a Geoteclymcal Services/Soil Testing&Inspection Services SITE Post Office Box 190537 - Boise, Idaho 83719 ZCON2SULTING, j� site.consulting.idaho@gmail.com - 208-440-6276 LLL • Stormwater disposal can be accomplished with a conventional infiltration trench. The system must extend to the free-flowing sand and gravel soil that was observed in the test pits at eight feet or more below the existing ground surface. Depth to free draining conditions may vary across the site and is to be confirmed at the time of construction by the project civil or geotechnical engineer. • The locally mandated maximum percolation rate of P=8 inches / hour is acceptable for design. Confirmation at the time of construction is required. We appreciate this opportunity to be of service. When appropriate, we would like to discuss continuing our role as geotechnical consultant during construction. Please contact our office if additional information or services are required. Respectfully submitted, SITE Consulting, LLC Bob J. Arnold, PE NAL FN �GXSTZ# �'Gfi�tA 3 OF e J. AR�� appendix follows. a a Geotechnica/Services/Soil Testing&Inspection Services SITE Post Office Box 190537 - Boise, Idaho 83719 site.consulting.idaho@gmail.com - 208-440-6276 CONSULTING, LLC CLIENT SUPPLIED LOCATION MAP q �m Q M N T-9 l T� �IIYi'F } �} e J ¢ Y h JXx reii r LO CL Ln 5 k c� { y w Landprodataxom a Geotechnica/Services/Soil Testing&Inspection Services Post Office Box 190537 - Boise, Idaho 83719 SI site.consulting.idaho@gmail.com - 208-440-6276 ZCON2SULTING, LL WORKING PLAN w *a �Fn= aU Supplied by client a. Geotechnical Services/Soil Testing&Inspection Services Post Office Box 190537 - Boise, Idaho 83719 site.consulting.idaho@gmail.com - 208-440-6276 ZCONIff"421SULTING, LL AERIAL PHOTO Test Pit Locations I h� Google Earth a Geotechnical Services/S011 Testing&Inspection Services SITE Post Office Box 190537 - Boise, Idaho 83719 site.consulting.idaho@gmail.com - 208-440-6276 CONSULTING.. LLC TEST PIT LOG Test Pit: TP-1 File #: 22824-A Client: Northern Land Holdings Date Excavated: 02/09/2022 Project: 3539 Locust Grove Road Excavated By: Wood Brothers Location: See Aerial Photo Logged By: , J. Meusch-SITE DEPTH SOILS DESCRIPTION (feet) 3/4" 112" 3/8" #4 #10 #40 #100 #200 %M LL PI 0.0-1.0 Brown, Moist, Firm, Sand, Gravel, Silt 1.0-3.0 Brown, Moist, Firm, Blocky, Sandy, Lean CLAY(CL) 2.0 100 98 1 98 1 97 1 85 1 61 1 51.0 1 17.6 307 10 3.0-6.0 Brown, Moist, Firm, Sandy, SILT(ML) 4.0 1 100 1 99 1 98 1 94 1 85 66 1 56.9 1 9.1 NP NP 6.0-10.0 Brown/Tan, Moist, Firm,Sand, Gravel, Silt 10.0 Bottom of Excavation @ 10.0' Sluffing Prevented further excavation No Ground Water Encountered Monitoring Well in Place 00 W un a Geotechnica/Services/Soil Testing&Inspection Services (� Post Office Box 190537 - Boise, Idaho 83719 / site.consulting.idaho@gmail.com - 208-440-6276 CONSULTING, LL TEST PIT LOG Test Pit: TP-2 File #: 22824-A Client: Northern Land Holdings Date Excavated: 02/09/2022 Project: 3539 Locust Grove Road Excavated By: Wood Brothers Location: See Aerial Photo Logged By: J. Meusch-SITE DEPTH SOILS DESCRIPTION (feet) 3/4" 1/2" 3/8" #4 #10 #40 #100 #200 %M LL PI 0.0-1.0 Brown, Moist, Firm, Sand, Gravel, Silt 1.0-3.0 Brown, Moist, Firm, Blocky, Sandy, Lean CLAY(CL) 2.0 1 1 100 1 99 1 98 95 1 82 75.4 10.1 27 11 3.0-8.0 Brown/Red, Moist, Firm, Sand, Gravel, Cobble 8.0-15.0 Red/Tan, Moist, Firm, Sand, Gravel, Cobble 15.0 Bottom of Excavation @ 15.0' No Ground Water Encountered Monitoring Well in Place CN an a Geotechnical Services/Soil Testing&Inspection Services T` Post Office Box 190537 - Boise, Idaho 83719 1 G site.consulting.idaho@gmail.com - 208-440-6276 CONSULTING, LLC TEST PIT LOG Test Pit: TP-3 File #: 22824-A Client: Northern Land Holdings Date Excavated: 02/09/2022 Project: 3539 Locust Grove Road Excavated B Wood Brothers Location: See Aerial Photo Logged By: J. Meusch-SITE DEPTH SOILS DESCRIPTION (feet) 3/4" 1/2" 3/8" #4 #10 #40 #100 #200 %M LL PI 0.0-1.0 Brown, Moist, Firm, Sand, Gravel, Silt 1.0-2.0 Brown, Moist,Very Firm, Sandy, Clay 2.0-6.0 Brown/Tan, Moist,Very Firm, Cemented, Silty, SAND,(SM)with gravel 2.0 100 1 97 1 96 1 88 1 78 1 58 1 43 35.9 12.6 NP NP 6.0-12.0 Brown/Tan, Moist, Firm, Sand, Gravel, Cobble 12.0 Bottom of Excavation @ 12.0' Sluffing Prevented further excavation No Ground Water Encountered Monitoring Well in Place O bn a. Geotechnical Services/Soil Testing&Inspection Services Post Office Box 190537 - Boise, Idaho 83719 �^ site.consulting.idaho@gmail.com - 208-440-6276 ZCON2SULTING.. LLC IDWR WELL DATA Was at 3665 N Locust Grove 015 ; P IDA1 ?DEPARTMEW OF WATEHRESOURCES WELL DRILLER"S REPORT a T - _ _. 1 GRUAIG MOOT NO 11. WELL TESTS: Ut t smw 0 ?S&P —lump -U er =.eta a Fi6Wba xrta�to � ER:ma Cttrl,E� rMC hwG kSTE '1,w 3f LOCATION OF WELL by legal description. S.to%as map tvA"Ic"n;rst apa.ttt,*frNi;taro E ,w. 12, L1TKOLOGtC LOG; �9Rwtbit repetrt ar a wrr4vrt3 iW) wata+ To awaits: L_Vtokw.Wskr Out i iitr#trrlRzts suY is a 4. Tt~**mitt t4jecton -01,ow 5. TYPE Of WORK owi#s mt t T C Doti METHOD ds F#f} ;ems Mal ( *F 7. SEALING PROCEDURES y41.dram#V*t °3 ,:.ry h tsaz p®py e, 8. ASING LINER: WATER MOUMAM 1l p. PERFORATIONStSCREEMS a M DRILLER`S CERTIFICATION Vwa #,_ftt at i+�eT WO til:'00 Srrr 10. STATIC WATER LEVEL OR ARTESIAN PRESSURE: G't,pttt t "countarad t. araipms putt or a-1 tr FORWARD W 7E G W ATFR FtFSOzK�S E .xtyes ittf�p�,# a� hA t1. Geotechnical Services/Soil Testing&Inspection Services S"SITE Post Office Box 190537 - Boise, Idaho 83719 Z �.i�+ I !1.-.#- �t{� ! site.consulting.idaho@gmail.com - 208-440-6276 CON:S:U L 1 I I G., LL IDWR WELL DATA 3545 North Locust Grove PARTMENT 4 J T OWNS WELL DR L "s REPORT .. t OF wow T 'u Mw wo' V <'� - - a �.r 07.11748 ,.. :_ bw fie MA ---- .a w + X ,'Ow pit At >�.-,.—�. _ s 17, u.v ... '"w" 0 r n .' Cd'ifaiki:#T7Cx1 - - x 4 A Vt W" FviNti 7;o - ftal31� .uuAe *x f N an Geotechnical Services/Soil Testing&Inspection Services SITE Post Office Box 190537 - Boise, Idaho 83719 site.consulting.idaho@gmail.com - 208-440-6276 CONSULTING, LL SOIL LOG LEGEND UNIFIED SOIL CLASSIFICATION SYSTEM (ASTM STANDARD TEST METHOD D 2487 FOR CLASSIFICATION OF SOIL FOR ENGINEERING PURPOSES DIVISIONS I=MPICAL DESCRIPTIONS GRAVEL& [775%-#200Jr GW1 Well-graded g7el, ravel-sand mixture,little or no fines. GRAVELLY JF_GP 11 Poorly graded gravel,gravel sand mixture,little or no fines SOILS 5-12%-#200 GM Sft gravel, ravel-sand-silt mixtures <50%-#4 >12%-#200 GC Clayey ravel,gravel-sand-clay mixtures SW COARSE <5%-#200 Well-graded sand,gravelly sand,little or no fines. GRAINED ir SP 11 Poorly graded sand,gravelly sand,little or no fines SOILS SAND& FSM I S 1—1tysand,sand-silt mixtures <50%- SANDY #200 SOILS >12%-#200 SC Fc—layey sand,sand-clay mixtures >50%-#4 91clay Lean clay-low to medium plasticity,gravelly clay,sandy clay,silty ORGANIC OL Or anic silt and organic silty clay of low plasticity SILTS AND MH Elastic silt,micaceous or diatomaceous fine sand or silty soil. CLAYS INORGANIC LL>50% 11 CH Fat clay-high plasticity FINE ML Inorganic silt and very fine sand,rock flour,silty or clayey fine GRAINED SILTS AND INORGANIC ❑ sand or clayey silt with slight plasticity SOILS CLAYS 1mr anic cla med.or hi h lastici or anic silt >50%- LL<50% ORGANIC y g p g #200 ORGANIC SOILS PT Peat,humus,swamp soil with high organic content ABBREVIATIONS AND ACRONYMS AASHTO American Association of State Highway &Transportation Officials HMA Hot Mix Asphalt Pavement ASTM American Society for Testing and Materials BH Bore Hole IDWR Idaho Department of Water Resources ISPWC Idaho Standard for Public Works Construction ITD Idaho Transportation Department NP Non-Plastic VNP Visually Observed to be non-Plastic PCC Portland Cement Concrete PCF Pounds per Cubic Foot PSF Pounds per Square Foot TP Test Pit USCS Unified Soil Classification System Nothing Follows can a Geotechnica/Services/Soil Testing&Inspection Services