Loading...
PZ - Geotech Report SITE Post Office Box 190537 - Boise, Idaho 83719 info@siteconsultingllc.com - 208-440-6276 CONSULTING, LLC Bruce Hessing January 18, 2023 Hesscomm Corp. Page 1 of 14 2338 West Boulder Bar Drive File 23791-A Meridian, Idaho 83646 Re: Geotechnical Recommendation Report Proposed Julia Subdivision 2435 North Black Cat Road Meridian, Idaho Bruce: SITE has modified this report to indicate your ownership of the property and plans for development. This report is based upon onsite test pits and labwork generated on samples gathered during onsite test pit excavation. Based upon the information herein construction of the planned residential subdivision is feasible. Our research and recommendations are included herein. We appreciate this opportunity to be of service. Should you have any questions or require additional information, please contact our office at your convenience. Respectfully submitt j0NA SITE Consulting, 1ST ���'i Bob J. Arnold, P 4 � Y-- 1/ 812023 OF I J° A� €3 l� N bA a Geotechnical Services/Soil Testing&Inspection Services SITEPost Office Box 190537 - Boise, Idaho 83719 info@siteconsultingllc.com - 208-440-6276 CONSULTING, LLC Geotechnical Recommendation Report Proposed Julia Subdivision 2435 North Black Cat Road West Talamore Drive - Meridian, Idaho PURPOSE The purpose of this investigation was to evaluate the onsite soil conditions, observe the groundwater's elevation, and determine the soil's engineering properties. SITE was retained to provide construction recommendations for the client who is the property developer. Specific items requested and included herein are earthwork recommendations, pavement and stormwater recommendations, allowable foundation pressures, and construction inspection / testing recommendations. AUTHORIZATION Authorization to modify a former report was received from the client on January 13, 2023. It is noted this project was started for another party and work was stopped when they withdrew from the project. Authorization to proceed and the use of the recommendations provided herein indicate the client's acceptance of the scope of work, warranty, limitations, and general conditions provided herein and within the submitted proposal. WARRANTY AND LIMITATIONS The exploration and evaluation of subsurface conditions documented herein is considered sufficient to form a basis for the provided recommendations. The provided recommendations are based on the available soil information and preliminary design details either assumed or furnished by the client. It is warranted that these recommendations have been promulgated after being prepared in accordance with locally accepted professional engineering and geotechnical engineering practice. No N other warranties are implied or expressed. Geotechnica/Services/Soil Testing&Inspection Services SITEPost Office Box 190537 - Boise, Idaho 83719 info@siteconsultingllc.com - 208-440-6276 CONSULTING, LLC GENERALBACKGROUND The project site is located on a 2.77-acre parcel located at 2435 North Black Cat Road in Meridian, Idaho. When completed the project will be accessed on the proposed Julia Avenue, south from West Talamore Drive. Julia Avenue is three residential lots west of Black Cat Road. A tax parcel number of S-2305252950 was found for this property within the Ada County Assessors Records using landprodata.com. The provided Concept Design Drawing indicates the planned subdivision will include approximately ten new lots for single family residences, a lot that includes the existing residence, numerous open spaces, and a single public (ACHD) right of way. A standard subsurface seepage trench or basin is planned for storm water re-injection. INVESTIGATION On November 12, 2021, SITE observed the excavation of two test pits at locations intended to provide full coverage of the subject property. Test pits were excavated where access could be gained while avoiding the existing horse corrals. Test pit logs and an aerial photo with test pit locations are included in the Appendix. In general, soils were observed to be similar in both test pits and consist of a non-plastic sandy silt and weakly cemented, silty sand with a four-to-eight-inch rootzone or organic layer. This overburden layer was six to seven feet thick in our test pit locations. At this depth, sands and gravels of the Whitney Terrace formation were encountered. These materials grade cleaner with increased depth and extend beyond the depth of our fifteen-foot dep test pits. Groundwater was encountered at fourteen feet deep in both test pits. Temporary wells were installed for future groundwater measurements. Well measurements have occurred since April 1, 2022 and are included in the Appendix. M a4 a. Geotechnica/Services/Soil Testing&Inspection Services SITEPost Office Box 190537 - Boise, Idaho 83719 info@siteconsultingllc.com - 208-440-6276 CONSULTING, LLC RECOMMENDATIONS Demolition The horse corals and numerous outbuildings are planned for demolition. Inspection at the time of demo should confirm removal of all foundation and slab on grade concrete. Any well or septic system encountered is to be closed as per IDEA and IDWR requirements. Septic tanks and drain fields below future home foundations are to be removed. Site Work Grubbing depths of up to six inches can be anticipated to remove most organic materials. Deeper removal may be required where large trees or bushes are present and along ditches and fence lines. Excavations caused by demolition, grubbing and removal of ditches, or over excavation of organic materials, or soft/wet areas are to be backfilled with structural fill. All subgrade soils present on the property can be used as structural fill on building lots and within right of ways. Compaction of any fill placed within building pads or right of ways must exceed 95% of the maximum dry density as determined by Standard Proctor testing. It should be anticipated that the Meridian City Engineering and / or Building Department will request these test results prior to or at the time of home construction. Structural fill must pass compaction testing and visual inspection for stability. Fill that passes compaction but is observed to rut or deflect under construction traffic is to be rejected and repaired. d" a Geotechnica/Services/Soil Testing&Inspection Services SITEPost Office Box 190537 - Boise, Idaho 83719 info@siteconsultingllc.com - 208-440-6276 CONSULTING, LLC Pavement Sections An R-Value sample has been sent to a specialty soil lab for testing. Based upon soils classification tests performed in our inhouse laboratory we anticipate an R-Value result greater than R=20. Based upon a Traffic Index of TI=6 and R-value or R=20 the following pavement section is recommended for Julia Avenue. Traffic Index TI=6 HMA 2.5" %" Base 4.0" Subbase 10.0" All materials and methods used in the construction of streets and sidewalks are to comply with ISPWC and ACHD requirements. Residential Foundation System The proposed single-family residential structures may be supported on conventional, continuous, and isolated pad foundations founded upon the native soils or upon structural fill extending to these soils. Based upon proper placement and compaction of structural fill, bearing pressures of up to 1500 psf are allowed for foundations founded on the native soils or upon properly placed and compacted structural fill. Either crawlspaces or slab on grade floors are acceptable. If fat clay is revealed at the foundation bearing elevation, a geotechnical engineer should be consulted. Slab on Grade Concrete Care must be taken so that all excavations below both interior and exterior slab on grade concrete are properly backfilled in accordance with the structural fill recommendations. Trenches and wall backfill areas are to be filled in lifts and benched each lift so that fill is not placed against a vertical soil face greater than three feet tall. Slab on grade floors, sidewalks, and pavements should be placed atop a mat of at least four inches of granular structural fill materials. Mat material should meet ISPWC 3/4" Ln base specifications. The mat shall be compacted to the requirement for structural fill. a Geotechnica/Services/Soil Testing&Inspection Services SITEPost Office Box 190537 - Boise, Idaho 83719 info@siteconsultingllc.com - 208-440-6276 CONSULTING, LLC Storm Water The proposed seepage bed must extend at least two feet into the native sand and gravel layer at seven feet deep in our test pit. The top of this layer was slightly cemented and therefore this cementing must be penetrated. A design perc rate of P=4 in./hr. is recommended for this project. ACHD will require confirmation at the time of construction. Inspection & Testing A qualified engineer or his representative should monitor fill placement to ensure the work is performed in accordance with these recommendations. For mass filling, compaction testing shall be performed on each lift of compacted fill with at least one test on each filled lot. Trench-backfill and right of ways are to be tested to ACHD requirements. It is noted that structural fill can pass compaction tests and still be unacceptable if pumping, rutting, or deflecting under vehicle or foot traffic. General Comments Testing and inspection services are recommended herein. Proper quality control during construction is required to confirm materials and methods and thereby obtain a desirable finished product. Monitoring and testing should also be performed to verify suitability of materials used for structural fills and to confirm proper demolition, subgrade grubbing, subgrade stability, and proper placement and compaction of fills. Any deviations from the herein described subsurface conditions must be brought to the attention of this consultant. This report has been prepared for the exclusive use of the client and their retained design consultants. Findings and recommendations within this report are for specific application to the proposed construction described herein and apply only to the property identified. APPENDIX FOLLOWS a4 a. Geotechnica/Services/Soil Testing&Inspection Services SITEPost Office Box 190537 - Boise, Idaho 83719 info@siteconsultingllc.com - 208-440-6276 CONSULTING, LLC APPENDIX A Location Photo Preliminary Plat Aerial Photo with Test Pit Locations Test Pit Logs (2) Adjacent IDWR Well Logs a Geotechnica/Services/Soil Testing&Inspection Services SITEPost Office Box 190537 - Boise, Idaho 83719 info@siteconsultingllc.com - 208-440-6276 CONSULTING, LLC LOCATION PHOTO Al s• Google Earth 00 bn Geotechnical Services/Soil Testing&Inspection Services SITEPost Office Box 190537 - Boise, Idaho 83719 info@siteconsultingllc.com - 208-440-6276 CONSULTING, LLC PRELIMINARY PLAT M "OISI.n-t�11S VI If m f� Him W11 I _ � 1 $C 0 0- F 3g go I V �•r $$ 3 � �p im, Supplied by Client C a, Geotechnical Services/Solt Testing&Inspection Services SITEPost Office Box 190537 - Boise, Idaho 83719 info@siteconsultingllc.com - 208-440-6276 CONSULTING, LLC AERIAL PHOTO with Test Pit Location dtc' O TP-1 , 0 TP-2 4 T�— Image from Google Earth O a Geotechnical Services/Soil Testing&Inspection Services SITEPost Office Box 190537 - Boise, Idaho 83719 info@siteconsultingllc.com - 208-440-6276 CONSULTING, LLC TEST PIT LOG Test Pit: TP-1 File #: 23791-A Client: Hesscomm Corp. Date Excavated: 11/12/21 Project: Julia Subdivision Excavated By: Wood Bros. Location: See Aerial Photo Logged By: J. Meusch-SITE DEPTH SOILS DESCRIPTION (feet) 3/4" I 1/2" I 3/8" I #4 I # 10 I #40 I #100 #200 %M I LL I PI 0.0-1.0 Brown, Moist, Firm, Sand & Silt 4-6" Rootzone/Organic Layer 1.0-4.0 Brown/Tan, Moist, Firm, Sandy, Silt (ML) 2.0 1 1 100 1 97 1 81 1 74 64 55.5 1 12.2 I N P I N P 1 4.0-7.0 Brown/Tan, Moist, Firm, Weakly Cemented, Silty, Sand (SM) 6.0 1 100 1 98 F95 1 88 1 78 1 58 1 38.8 1 15.5 1 N P 1 N P 7.0-15.0 Brown/Tan, Moist, Firm, Sand, Gravel, Cobble 15.0 Bottom of Excavation @ 15.0' Ground Water Encountered @ 14.0' Monitoring Well in Place r-I e—� b a4 a. Geotechnical Services/Soil Testing&Inspection Services SITEPost Office Box 190537 - Boise, Idaho 83719 info@siteconsultingllc.com - 208-440-6276 CONSULTING, LLC TEST PIT LOG Test Pit: TP-2 File #: 23791-A Client: Hesscomm Corp. Date Excavated: 11/12/21 Project: Julia Subdivision Excavated By: Wood Bros. Location: See Aerial Photo Logged By: J. Meusch-SITE DEPTH SOILS DESCRIPTION (feet) 3/4" I 1/2" I 3/8" I #4 I # 10 I #40 I #100 I #200 I %M I LL I PI 0.0-6.0 Brown, Moist, Firm, Sand & Silt weakly cemented at bottom two feet 4-6" Rootzone/Organic Layer 6.0-15.0 Brown/Tan, Moist, Firm, Sand, Gravel, Cobble 15.0 Bottom of Excavation @ 15.0' Ground Water Encountered @ 14.0' Monitoring Well in Place N rl a. Geotechnica/Services/Soil Testing&Inspection Services SITEPost Office Box 190537 - Boise, Idaho 83719 info@siteconsultingllc.com - 208-440-6276 CONSULTING, LLC ADJACENT IDWR WELL LOG Furm 238-7 W07 IDAHO DEPARTMENT OF WATER RESOURCES WELL DRILLER' DEPORT 1,WELL TAG NO,Df]�614I �} 12 STATIC WATER LEVEL and WELL TESTS; �l� grilling Permit NO. '�'S�.M 01- „-, '7� Mpdh fxsk uatue ene�•' F ((ly--.*............Slada w9led level�fo,C� Ylaiaw•rL]N or l-j--lcn wvM ��t Bol4arn bare lawrta ('F} z OWN rzp- --- __-- basmba ecr ass part Name/lr] !"l am / tI Well wl; Test hWO'Jhd'- Addrasi `~ C' OrarJswn lravl r iaOdd Jrprn) mnuk3 n P p ea�kr rW aMslan � Q &WELL LOCATION: 7 p a_W, L3 or Soulh❑ Rge. JF E=E] or vtst@ IWturgtradltym9lorw:onvnamts; - / 49-LJ7HOLUCiIC LOG sndloc raDalris or abandanmur& 114 f 1 A 'gge-114 a 4r a Frde I La I Ramorq�,IrmlopY mr Uurshppc4 cf nralrF ar n C fiLai CBr�rlyADA __._ . ."a l a6simonmerr�wrrlor grpp, ._ rH q a A LaL m '" rr11 0".anm .........._.. Lang, e e� ar [gag n�Caa�lmculn� f A AddresioYWO&Le 'f' rkme- Cdr Lat Rk. St b-Namur r' cr 4.USE: } � Z L7bmasu ❑rdrY eno ❑momix ❑Itr pmGult ❑Tw mel ❑1*01m1 p ocn- 5,TlPfi OF WORK 1....... ....... 0 Nc —it Q Reprmocrmr•nl rri7 tAmtlify eu-,wy u.�tl f �dH1LL ME7HOfl: 1X rr RoL-y 2 Mud RPIary Cabo ❑Dftr..---- -.._......._ ... 7-SEALING PROCEDURES: Uczr n7 'Flan 4 o II us: :Ec rry Pdesearl me W E y �}^lr 9.GASINU�LINER: LY4TEI�RTw Li*-rr Ram* Frrs. ._ t Th ta r��e T°t e�fi�lrn '7��ex+ret t7�ru lrn-Line �r.3ard wioW rr / la ❑ ❑ ❑ ❑ €Q ❑ r. 9O la ❑ Q ❑ �, --3 a I: a ❑ Was drhT ahoe ilsad7 d Y 12 It'&hW Dpplko GES 9.PERFORATIONSISCREENS: per allur4 ❑w ❑N telotl'ad Matmf=Lffed scam 17Y QNTypp " MMhhdrliN$In bbn Mr•! Fromm} 7o9r0 3m san Nrcmborm Qa me" G-W ar&h dda C[Yri Ih ta§rgEheS oC /,!} id-MLLER'S CERTIFICATION= Ime eer'Fy U%sl oit mlramm wag ewswmion stsrpd m*Era[omplled with er Ine L�wuw rig was removed. LeMgeY OF He9aFip!�Lark]�r gIT�7pip� 1 4 i Packer❑Y ❑N Tyroe CumRony tdamo LLI Ca Nv� i 111-FJi PACK- •Prirpy 13rj1pr 139a Fh.Waw" I F—tnF %Ii} over, fr) Phb-. hw4lod 'Driller bad omp- 11-I'LU ING ARTESKIR: OPKaW i Dgo Fhvwng Aricsran?d Y Pfl N A4wAmPnosom IP57G)T •SlyoalumM Principal t]rllLar and r;y operairr are required. (Y'� Ewwibaconlraldeoice_- - — bA a Geotechnical Services/Soil Testing&Inspection Services SITEPost Office Box 190537 - Boise, Idaho 83719 info@siteconsultingllc.com - 208-440-6276 CONSULTING, LLC ADJACENT IDWR WELL LOG o ficc une t]nly r-7.3a4 IDAHO DEPARTMFN1"OF WATER RESOURCES inspwc4 by W951-M WELL DRI;LLER'S REPORT Twp k.ec 114 _114 _114 L OXILLIlNG FElTM.I r Na u - 11.WELL 7ESirx LW: U m1: Other IDWR No. ^' Puw 0 R-dilar 0 AVr El Fluwin Attaasian 2.OWNER. FlUG Kum liriehton Cornomion Address 12426 West H=ILwer Fkive_Suite 220 City lkim swc ID Tap 83713 Wmer'Tcmp. nnlM hole rclrt}+, X LQCATFON OF WELL by lepl deseriptian: Water Qmlkry moor oanuncnrs• Sketch map location tmiStlgm with wriMn iwzitxl IkMh first Wmcr 15lmpuntend N 12_LrrHOLdGTC LOG:(DeaMillm r4/.Ira w trbandmument) rTIM T--p.3 hloiilt E of south ❑ Rgtt. I E&W ❑ ur W', ti ® wtuaer 14 F — &xe From To Pe—rlaiUdu W WzWrQm11y&Twp N 4cc_ 3 114 NW U4 SW 114 �` IF IF-- 8" 0 4 1`01 l w4 Top sal 8" 4 80 Filled with 33'[-rranular Berrumite 5 Gov't lot CoW1ty ADA Let: Long! : i Addrenof Well Site :�irLt 'C—E L i �I�1�^y_ �.• CityW,111DIAN .ey as mwr sivaa x. a1e i,t. Blk_ Sub.Name 4.USE: -- Domestic ❑M.r cipul [] W*Ao, ❑ fimgxitxi ❑ lhmmak ❑lajealkmt ❑ (Aher .._..._.__...__.... S.TYFE OF WORK cbe&ulI that apply {Replacement etc.l ❑New WeH❑Madi fy®Aban&rimznt❑1 PtheT� 6.DRILL MVTHOD ❑Air Rotary©Cable❑Mud Rotary,❑OEher 7.SEALING PROCEDURES SEALTILTLR PACK Amouwr METI M) Matmisl rrnm ro q*Uw wnµls Was drive shoe used? ❑Y ❑ N Yjur Lh 0 !,] Wwa Mvcahm&cal tceted?El V 0 N lk—r i1'Ai#ft �tiag t.lrpr Welded Tltrudod &Iarau I 1� ❑ Q ❑ ❑ ❑ ❑ ❑ lMOmfHrud*c Length of-1'ailpitx 9.PERFORATTONSdSC'REENS 11c):.n. npldad Depth:0 }Crruftaiulu Mv.(hw %MM I gu I 4= C:txn kmcd01114?1)2 ❑ Saecns SGMM I)TM 13,DRILLER'S CERTIFICATION U4Ve orrti6 tiwt oll minimum well wustrt"ion atm drmds were From To Idol Six Numhn 1),sax+t* tiisierisl Ce:in I.:tom txvopliud wish nt the rink.tlx rid;WM n2riuxrd_ El El ri ❑ Puns Name SUS WcHdrillinu&Putun Gs Firm No.212 Ij Cl IQ.9TATTC WATER LEVEL OR ARTESIAN Film[HTit:ial 4 Date, _- MSSURE: . - ' 1LUb,l—P'-4 Aniniw Prersa-e lh Supervtx is or Up uatMr DwoIV flow enopuntercd=�tit IkNMIV. &cuss port or control t81p°°°OYFi4tOtikLl&Operw4l tlevit F': DwV191ilQTkw.!P.18AM Nothing Follows a Geotechnical Services/Soil Testing&Inspection Services