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Home My WebLink AboutDaves Creek Geotechnical Investigation 1991NOI~V~S ~OS ~~~HJ SaAYO X~IHO~OV X~H3N3 V~SV~ NOI~V~I~S3ANI ~JINBJ3~03~ I I I I I ,I I I I I I I I I I I I I I GEOTECHNICAL INVESTIGATION ALASKA ENERGY AUTHORITY DAVES CREEK SUZSTATION DRAFT REPORT Prepared for: ALASKA ENERGY AUTHORITY P.O. Box 190869 Anchorage, Alaska 99519-0869 Prepared by: Arne Tikka Mike Tauriainen,P.E. NORTHERN TEST LAB Box 937 Soldotna, Alaska 99669 February 1991 Project No. 91019 t Lab February 2S, 1~91 'l'om Arminski Alaska Energy Authority P.O. Box 190869 Anchorage, Alaska 9~51~-0689 ~101~ Subject: AEA Daves Creek Substation Geotechnical Investigation Draft Report Tom: Enclosed are two copies of our draft report for subject project. The work was performed in accordance with our January 18 & February 5, 1991 proposals and discussions with you and Stone & Webster Engineering Corporation personnel. 'l'he recommendations contained herein reflect our understanding of the proposed project. Alternate solutions to those we have suggested may be appropriate and we would appreciate the opportunity to discuss them with you. Please call if you have any questions regarding this report. We encourage your careful review and comment. The final report will be completed after your review of this draft. Sincerely, a --r: vi/'! ~-!~ ! --~~ ,_ Arne Tikka Project Engineer llb:aeaaaves.rpt Attachments 35186 s~UR HWY SOLDOTNA. AK 99669 ,907]262-4624 FAX 252-5777 Ar.arvtlcal, Environmental. Geotechnical. C,:;nstructlon Mater1als Tescng DAVES CREEK SUBS'l'ATION GEOTECHNICAL INVESTIGATION CONTENTS l. INTRODUCTION • • • • • • • 1.1 Background •••• 1.2 Scope •••••••• 2. SITE TOPOGRAPHIC AND GEOMORPHIC CONDITIONS. 3. FIELD !NV EST !GAT ION. • . . . . . . . . . . . . 4. LABORATORY TESTING • . . . . . . . . . . . . . . . . . . 1 1 1 2 3 3 5. SOIL, GROUNDWATER AND SURFACE WATER CONDITIONS • • • 3 6. EXIS'l'ING UTILITIES AND O'll:l.ER SITE CDNDITIONS • 4 7. CONCLUSIONS AND RECOMMENDATIONS ••• . . . 7.1 Bearing Capacity ••••••••••••• 7.2 Footings ••••••••••••••••••• 7.2.1 Alternate Footing Recommendation 7.2.2 Drilled Piers ••••••••••••• 7.3 Fill and Back£ ill. • • • • • •• 7.4 Frost Action ••••••••••••••• 7.5 7.6 7.7 Drainage • • • Construction • Corrosion. 8. CLOSURE. ATTACHMENTS . . . . . . . . . . . Soil Boring Log Legend. • • • •••••• Drawing Al Soil Boring Logs. • • • • • • • • • • • • Drawings A2-5 Lab Test Results. • • • ••••••••• Sheet Bl-2 Site plan with Soil Boring Locations. Drawing C Shallow Footing Details • • • • • • ••• Drawing D 5 6 7 7 8 9 10 10 11 11 12 1. INTRODUCTION 1.1 BACKGROUND The Alaska Energy Authority (AEA) is proposing to buila an electrical, power substation adjacent to the existing Chugach Electric substation, near mile 40 of the Sterling Highway, east- northeast of Cooper Landing, Alaska. Design snow and wind loads are unknown for this site. 'l'he proposed substation is locatea in UBC Seismic Zone 4. According to AEA personnel, subject property belongs to the National Forest Service. 1.2 SCOPE Northern Test Lab (N'l'L) was retained by AEA to conduct a sut:Burface soils investigation, laboratory testing. and analysis of the data sufficient to prepare a geotechnical report of foundation soil characteristics, static bearing, static settlement, and related properties, for design of improvements to the proposed Alaska Energy Authority substation. The work was performed in accordance with our discussions, our January 18, 1991 proposal, our February 5. 1991 proposal, and our standard geotechnical procedures. We understand that improvements to the proposea substation will consist of towers and poles founded on drilled piers, and other structures designed with conventional spread footings. Stone & Webster Engineering Corporation personnel inaicate the maximum sustainea vertical loaa may be on the order of 2000 -3000 psf. We understand that moderate frost heave (say two inches) can be tolerated by the proposed facilities. AEA Daves Creek Substation Draft Report Page 1 2. SITE TOPOGRAPHIC AND GEOMORPHIC CONDITIONS The proposed substation is located in the Kenai Mountains along the Chugach Mountains geosyncline. Sedimentary rocks of Jurassic and late Cretaceous age were highly deformed and partly metamorphosed durina post-Paleocene time in this area (DSGS Professional Paper ~ . 542-E). The area was uplifted and eroded several times auring the 'I'ertiary Period, and possibly continuing into the Quaternary Period. Unconsolidated glacial and fluvial deposits presently overlie the bedrock in most places except on the steeper mountain slopes. The surrounding Kenai Mountains make most of the region very rugged terrain, characterized by numerous glaciers and glacial worked topography. 'I'he area of the site lies in a narrow, glacially scoured valley near the center of the Kenai Peninsula. Soils in the area of the site appear to consist of fluvial and/or glacial-fluvial deposits. Based on relative soil boring elevations, the area of the pro_[::€rty investigated appears to be sloping gently toward the southeast, however, the actual terrain in the area of the soil borings was quite variable. Quartz Creek flows in a southwest airection just northwest ot tl:e site. Vegetation consists of small diameter spruce and some larger aiameter asper, and cottonwood. Ground cover appears mostly gravelly, borings. however, some surrace organics were encounterro at some Based on the terrain and vegetation, flooding ot the site shoula not be unexpectea. 'I'otal reliei appears to be less than five feet in the area of the soil borings. elevation is 600 feet above MSL. 'I'he approximate site The site is bordered on the south by the Chugach Electric Substation, which is aajacent to the Sterling Highwa1. Cther surrounding property appears undevelopea. AEA Daves Creek Substation Draft Report Page 2 3. FIELD INVESTIGATION The field investigation was performed December 11-12, 1991 using a Kraxberger Drilling, truck-mounted B-53 mobile drill rig. ~~o soil borings <SB 1 & 2) were advanced to 30' and four were advanced to a depth ot 15' using a·· OD hollow stem ausers. Representative samples were obtained .:rom 1.4'' split spoon samplers driven into undisturbed material belc'ri the rot tom of the auc;;ers .,.,.i th a 140i hammer dropping 3U", the Star:dara Penetration Test. Soil types and blow counts are shown on the attached test hole logs, Drawings A2-5. Each sample was visually characterized in the tield and further verification and classification was performed in the lab. Approximate boring locations are shown on the a ttacheci site plan, Drawing c. Borings were located by N~'L personnel, during the field investigation, according to a site plan prov1ded by AEA. ~·he actual locations were measured from existing area improvements using a fiberglass tape, but were not surveyed and are approximate only. Final boring locations were staked and labeled. 4. LABORATORY TESTING Approximately 30 samples were retainea from the soil borings and selected samples were tested for grain size. Test results are shown on the test hole logs and on the laboratory test results, Sheet Bl. Similar soils were combined for testing ana are noted. on the summary sheets. 5. SUBSURFACE SOIL, GROUNDWATER AND SURFACE WATER CONDITIONS Soils encountered while drilling were variable and. consist mostly ot noncohesive sand and gravel mixtures with varying silt content, AEA Daves Creek Substation Dratt Report Page 3 apparent cobble layers, and sand layers. Surface organics from o.s• -1.0' thick. were encountered in SBs 3, 5, & 6. An approximate one and one-half foot thick. cobble layer (cobbles to four ir.ch diameter or more with sar:c, gravel, and silt filHng :::.r: voids) was encountered within the tof four feet in SB 1, 2, & 3, ano cobbles were encountered from the surface to four feet deep in SB 4. Some sticks and organics were obsePied in the split spoon sample from 5-6.5' in SB 2. Soft sand and organic silt were encountered from 4.5-6.5' in SB 5 resulting in a low blow count <11 blows per foot) from 5.5 -6.5'. Some soft to moaerately dense gravelly sand was encountered from 4.0 -11.0' in SB 1 <16 blows per foot from 5.5 -6.5'). Other soils appeared variable and consist oi sand/gravel mixtures with varying silt content, coarse gravel or cobble layers, and sand layers. A groundwater table was encountered in all soil borings at depths ranging from 8.0 -12.5 feet. The groundwater table could, ana probably does, rise to higher levels and could affect foundation bearing capacity and performance. Frozen soils were encountered in all borings to aFproximately one foot below the grouna sur race. SB 2 & 3 are located on, or adjacent to, a drive kept clear of snow, ana had frost p;:netraticn to 6' and 3', respectively. No surface water was encountered in the area of the borings, however, Quartz Creek flows just ~~ of the site, as aescribea previously. ~he site appears to lie within the flooa plain of Quartz Creek., and while the tlooa potenLial appears to be significant, it was not a part of this investigation. 6. EXISTING UTILITIES AND OWER SITE CONDITIONS Electrical transmission lines and an electrical substation are located directly south ot the soil tor ing locations. 'l'he aajacer1t AEA Daves Creek. Sur..station Draft Report Page 4 , . Chugach Electric Association (CEA) substation was originally constructed about 15159. CEA was contacted prior to tne soils investigation for setback r eq ui rem en ts. CEA personnel were on site during the field investigation and inoicated setback req.~irements from the transmission line and substation. No other apparent u~ilities exist onsit~ According to CEA personnel ons1 te during the t iela i nves t.l sa tl on, some fill and possible debris may have been buried aaJacent to CEA's substation, in the area of SB 2 & 3, auring original consuucr.ion. 7. CONCLUSIONS AND RECDMMENDATIONS We understand that proposed improvements may consist of. towers or poles founded on drilled piers, or other structures using conventional footings for the foundations, and our recommendations are based upon that assumption. The soil conditions at the site generally appear to be suitable for this type of construction, provided these recommendations are followed. The op1n1ons expressed with respect to soil characteristics incluae only qualitative considerations of the probable aynamic characteristics of the foundation soils. No deep seated hazards related to time dependent settlement under static loads or liquefaction uncer dynamic loads are t:reaicted on tne basis of the d3. ta and our knew ledge of the local area. However, limi teo areas of shallow (0-7') soft soils may experience some gravity or seismic related consolidation. The relationship of the structure tc the foundation soi 1 rr:ass in terms of ground response unoe r ear tllq uake load is not part of the scope of this investigation. It is our opinion based on the data that ground response will be t.hat associated with moderately dense fluvial deposits resulting in strong ground motion. A numter of borings inoicate appare~t. sott and/or organic soils AEA Daves Creek Substation Draft Report Pase 5 which should be compacted or excavated prior to placement ot structures. We recommend that sufficient time, as well as unit prices, be allowed for identification and exca·;ation of any unsuitable soils at the time of construction. It is our opinion that this will be the most efficient resolution of the apparent problem. However, if the owner wan-es to further cefine tte extent or u n s u i t a c 1 e J.: 2. L e r i a l f or tid a i n g ;: ,__; r p o s e s , t e s t .::-: o 1 e s u. c a v c. t e c using a backhoe, a resistivity survey, or similar technique could provice better definition of the unsuitable soils. 7.1 BEARING CAPACITY A maximum allowable bearing capacity of 4000 psf is recommended for the moderately dense to very dense sands and gravels below approximately four feet, provided any loose soils are adequately compacted or removed. Any soils that do not respond to compactive efforts should be replaced. Because of the relatively shallow groundwater table and the probability that it will rise, the allowable bearing capacity should be adjusted by a groundwater correction factor tor some footings: Cw = 0.5 + 0.5[0w/(Df +B)] < 1.0 where Cw = grounawa ter correction factor Dw = depth of wa. ter table below ::ooting Df = depth of footing bel CJ.oJ nearest surface B = width of footJ.ng Allowable bearir.g capacities may be increasea 33% fer wino, se1smic or shock loadir:g. The predicted maxirr:um total settlement shoula not exceed one inch under the design loaaing conai tior.s, proviaed the recommendations of this report are followea. Differential settlement could be up to 3/4 of the total. A~A Daves Creek Substation Draft Report Page 6 7.2 FOOTINGS All peri meter he a ted footings should be placed a mini mum ot 3 1/2 feet below final exterior grade (unless a shallow insulated footing system is used in which case the minicum depth shoulc be lb inches). 1'he hlinimum depth for interior footlngs shcula be 18' incr:es. 'l'he recommended minimum width of continuous footings is 18 inc.hes. 'l'he recommended minimum dimension of isolated footings is 24 inches. Interior footings may be shallower, and all footings may be r.ar rower provided the recommended bearing capacity is reduced proportionately. Non-bearing stern walls may be on the order of six inches wide. Unheated shallow footings founded in these soils may heave. 'I'o reduce or prevent significant heaving of unheated footings a variety of construction solutions may be appropriate, depending on the design features and allowable heave toleration of proposed improvements. Heaving of unheated footings may be reduced by one or a comuination of the following: 1) found footing below the maximum depth of freeze and prevent uplift along sides of footing (this option may be aifficult due to relatively shallow depth to water tacle), 2) insulate to prevent frost penetration into frost suscepticle soils under footings, and 3) replace frost susceptible soil witt NFS soil to below the maximum depth of treeze. All footings sho~ld bear on on competent and compactea ~FS cackfill, at least 12 inches thick. Allowable bearing capacities mav be increased in accoraance with Section 7.3, FILL AND BACKFILL. 7.2.1 Alternate Footing Recommendation An alternate shallow, insulated. footing system may be considerea for heated buildings consisting of a footing monolith1c with the floor slab, or a short stern wall. 'lhi s footing should be set to a AE.A Daves Creek Substation Draft Report Page 7 minimum depth of 18 inches. Two inches of extruaed polystyrene insulation should be pla.cea vertically against the outside of the foundation, then extended outward a sufficient distance to avoid frost penetration beneath the footing, as shown on Drawing D. The cost of additional ins~lation is uscally more than cfrse~ cy the reduced fou.naa t.icn aectr .. For unheated sr,allow toot:;.ngs the insulation r:-.csr. ce -::r;.:.cr;er (minimum of 4 inches), must be continuous uncer the enure :::ccr_ing, and must extend significantly beyond tne footing peri~eter. 7.2.2 Drilled Piers 'l'he allowable end bearing capacity for piers can be taken as 4000 psf given the following conditions and assumptions: -depth: 10'+ -min. ciarn: 24" -safety factor: 3.0 in shear -placed near or into water table -angle of internal friction: 330 Shaft friction can be taken as 500 psf for sustained loads ana 1000 psf for transitory loads. Maximum anticipated settlement under these conditions may be expected to be one to two inches. The lateral earth pressure (total pressure on a ur:it of a vertical plane extendin<; :rom the surface to a depth H) can i::-e taKen as: active, Pa = lb.5H2 Therefore, given an effective aepth of nine feet (allowing one toot of disturbance on a ten foot bury), a aiameter of two feet., ana a satety factor a: :.tuee, the resistance c:o laterd aisplacer..ent hOL..lc be 11,340# actin; three feet up fro~ ~~e base. for ::ansitory ~caas AEA Daves Creek Substation Draft Report Page 8 this could be increased to 15,000#. Drilled piers foun~ed at or above the water table woulG reduce construction problems and associated costs. Working below the water table would likely require casing of the hole and use ot a slurry (drilling mud) to control sloughing. Belling is prot.acly not feasible because of tne cohesionless soils, therefore set.s of two piers, tied at the top, may be desirable. 7.3 FILL AND BACKFILL Fill and backfill under footings and slabs shoula be NFS, flaced in maximum loose lifts of nine inches and compacted to at least 95% of maximum density per ASTM D-1557D, with a correction for oversize particles in accordance with Alaska 'I'-ll if appropriate. Backfill under footings should extend from the bottom edge of footings to undisturbed soil at a maximum slope of 1:2, horizontal to vertical. The upper six inches of any backfill below footings or slats should have a maximum size limit of two inches. Final founaa tion bearing surfaces should te carefully inspected prior to placing relnforcing steel and concrete to verity that any loose soil has been compacted or removea and any frozen soil, debris, or organic matter nas been removed. Irr.ported fill/bacKfill shculd be reascnably w-ell-gr<;:.aed ar.a able to be compacted tc a tight, unyielding surface. Fer local ~ater1al meeting the tollcwing graaation and cor:<pacted to at least 95% or tne maximum density, an allowable bearing capacity of up to 50 C.G psi may be usee at the upper surrace of the bccKfill proviaec tne loading of the in situ so1ls does not exceea the allowable noted ~ncer 7.1 BEARING CAPACI1Y. Soils not meeting th1s gracation shoulc be evaluated on an inaividual basis. A~A Daves Creek Substation Draft Report Page 9 Sieve 3" 1" #2LG Percent Passing 100 70 -100 35 -75 G -5 The in-situ sc1ls at the bottom ot an excavation shoulc remain undisturbea, or if disturbea be rer::ovea, prior to placing any backfill on them. The onsite soils within approximately 6-8 feet of existing grade are generally not suitable for backfill material below footings or slabs due to the silt and cobble content. Footing and foundation wall backfill not supporting slabs or pavement should be compacted to 85 -9(J% of maxi mum density. Care should be utilized adjacent to walls to avoid overcorr.pacting backfill and laterally displacing foundation& 7.4 FROST ACTION The depth of frost penetration tor a site is aependent on soil conditions, exposure and weather. For the sanay/gravelly soils encountered, with a surface kept clear of snow, normal cepths ot freeze can be e:;pected to approach b-10 feet, ana 10 feet or more for NFS backfill. 'I'he actual trost pE:r.etration adjacent to pro:p;rly designed foundations of heated buildinss will be muc~ less. 7.5 DRAINAGE Minimum slopes of 5% for a mini~um cistance ot lG feet should be provided away frcm builaings to promote arainage. Any concentrated drainage shoulc be directea away from builaing foundation& The final grades should be carefully consiaered to promote surface AEA Daves Creek Substation Dratt Report Page lU drainage and avoid pending and surface water infiltration. Onsite soils appear free draining to the water table. 7.6 CONSTRUCTION Soils are mostly nonconesi ve and CL:tS in tne s1 te sands ar.a gravels can be expected to slough to at least 1:2 slopes and nay do so without warning. Com:paction of backfill and frost sl.l.sceptibility of soils s.Goula be carefully monitored during construction. The existing soils at the bottom of any excavation should be maintained in their natural condition, or carefully compacted if necessary. For footings that cannot tolerate a total maximum settlement of greater than one inch or differential settlement of more than 3/4 inch, we recommend over excavating, proofrolling, and placement ot properly compacted backfill material. Potential occurence of debris, soft sand, and organic silt deposits exists throughout the site. Materials of these types were encountered in SB 2 and SB 5. As mentioned previously, some construction detris from original construction of the aaJacent CEA substation may te buried. 'I'he groundwater table may, ana i.iOSt likely WJ.ll, rJ.se tO higher levels c:..;ring otter timee of :::e year and may sigr..:..f 1cantly atfect construc~1cn activities. Sor..e aewatering or excavations or aiversion of runoff may be necessary. 7.7 CORROSION The soils in the Cooper Lanaing area typically have not shown to be of a very corrosive nature. However, all underground materials should be correctly selected, properly installed and carefully inspected at the time of installation to assure satisfactory serv1ce AEA Daves Creek S~Dstation Draft Report Page 11 life. The need for cathodic protection, coating, or other protection of the underground materials should be evaluated. 8. CLOSURE 'I'his report is t.asec on oc:r unaerstc.r.:::::..ng of tne prcposea s::.r.t..:c:.:.... and performance criteria. Deviations from these criteria coula alter our recommendations. Our recommendations are cert.:nnly nvt all inclusive ant various other techniques and options ~ay te desirable. We would appreciate tr:e opportunity to rev1ew ana evaluate any significant foundation related changes. Due to the variable nature of soils and occasional soft soils on the site, it is our opinion that subsurface conai tions may vary considerably, and in some places may require extra excavation and/or proofrolling. The actual extent of soft soils can best be determined at the time of construction. We recommend that sui table provision be made in the contract documents to accomocate varying earthwork conaitions. Finally, we recorr:mend the site be carefully checked by a qualitied engineer during construction to verify that conditions are as anticipatea in tne design. We are available to aiscuss th1s report in more detail with the owner and/ or ~is representatives. AEA Daves Creek Substation Draft Report Page 12 I STM.VARD SYMBOLS ORGAPHC MATERIAL COBBLES & BOULDERS CLAY SILT SAND SRA'JEL ~11?LER TYPE SYMBOLS: s~ . Ss • Sl • S!': • • Sx. Sl. ~ .. ~1 . CONGLOMERATE SAilDSTOiiE 1.411 Split Sl:oon with 47# Hamr:~er 1.4" Split Spoon with 140# Hammer 2.5" Sclit Spoon with 140# Hammer 2.5" Split Spoon with 34D# Hammer 2.011 Split Spoon with 140# Har.uner 1.411 Soiit Spoon with 340# Hammer 2.511 Spiit Spoon, Pushed r.4 11 Spiit ~on Oriven with Air Hammer 2.511 Split S,."'on Oirven with Air Har:-!!ler lGilEOOS ROCK IIET AI«JRPH I C ROCK ICE, MASSIVE ICE -SILT 'JP.G~f-;IC SILT Ts ••• Tm Pb •• Cs ••• Cd ••• Bs ••• A G SA:mY SILT Sll T GRADWG TO SAilOY SILT SANOY GRAVEl, SCATTERED COBBLES (ROCK FRAGMOITS) INTERLAYERED SAill & SA~mY GRAVEL . 3iLTY CLAY •/TRACE SA~U Shelby Tube Modified Shelby Tube Pitcher Barre 1 Core Barrel with Single Tube Core Barrel with Double Tube Bulk Sa:lUie Auger Sar:~ole Grab Sa:~ole •:JT::: Sar.~oier types are eitt·.er .,o::ed above the Boring log or adjacent to it at the respecti·;'! !a.;ole depth • TEST HOlE ~"t.MBER -TH 2 DA'IE DRillED 5 June 1961 ........-SAMPLER TYPE All Sa~ies Ss ORG~~;IC HATEF.I .t.:.. (PT) Ccrsiderable ~isitl e ice 0' -7' ICE -"L-ICE DESCRIPTION FROZEN . INTERVAL --_ss STRJ..TA CP.AXGE _... .• ~ ~~.0 Cd 30 .0 (ICE~11 -· G) BECq8-.:K (Schist) (BX) T.D. 'IUTAL DEP'IH DRIU.ED * W.D. -Whi le Jrilling: ~.~. -After Drilling Nti~ t ;;e;;·;;L·'·i it!"st ,.oca 46 Soil Boring Log Legend Materials and Quality Control Teating C~ECSEO: D!E: ~~-~~:~------~ Pt\~J.NO .: Norltlern les t Lab An11ly tio111., Environmenta 1., Geoteohnio111., Construction Materials Testing SB 1 2-11-9 1 Sandy GRAVEL w/Sm. snt, Gray I Soil Boring Log Date: 2-18-91 lniti11ls: A.T. AEA Dave·s Creek Geotechnica 1 Investigation Soale: 1" = 3.0' SB 1 Sheet: A2 of 5 Dense, Froz:en or Sl. Mo;st, (GM) Ss SAND, Ot;ve, Dense, Wet, (SP) (Cobbles to 4" ;n Auger Return) G) 16 Gravelly SAND, Ql;ve, Mod. Dense, Sl. Moh~t, (SP) @75 Sandy Gravel w/Tr. to Sm. snt, Mo;st, (GP-GM) Water@ 12.5' W .D. (Cobbles to 4" ;n Auger Return) @ ~0+ Blows for 6 ·· (No Reoovery) SAND, Ol;ve, Dense, Wet, (SP) @e6 Sandy Gravel w/Tr. sm, Ol;ve, Dense, Wet, (GP-OM) T.D. Norlltern lest Lab Analytical~ EnYironmenta 1 ~ Geotechntca 1 ~ Construction Haterials Testint SB 2 2-11-91 Sindy GRAVEL w/Sm. Silt1 Gray 1 Soil Boring Log Date: 2-18-91 Initials : A. T. AEA Deye·s Creek Geotechnica 1 lnY•stitation Seal•: 1" = 3.0' SB 2 Sheet: A3 of 5 Froztn 1 (GM) Ss Samt u Abovt (Cobblts to 4"1n Au9tr Rtturn) (Cobblts or Co.rst Oravtl W .D.) (!) 84 @100 SAND w /Sm. Gravtland Tr. SHt 1 SAND w/Sm. Silt1 Olivt 1 Froztn1 (SM) ("'/Stick~ ind Org~'ic Debris in Simplt) V. Dense 1 Wtt 1 (SP-SM) Wittr@ 8.0' W.O. @s6 SAND w/Sm. Oravtland Tr. S11t 1 Olivt 1 Dtnse 1 Wtt 1 (SP-SM) @32 SAND 1 Olin 1 Dtnst 1 Wttl T.D. (SP) @98 Sand~t~ OR AVEL 'W' /Sm. Silt 1 Olin 1 V. Dens• 1 W tt 1 (OM) Soil Boring Log Dat•: 2-18-91 Norlltern lest LDb lntttals: A.T . AEA Dave·s Creek Seal•: 1 " = 3.0' Ana lv ttca 1, Envtronm•nta 1, G•ot•chntca 1, G•ot•ohnioa 1 lnv•sttgation Construotion Hater a ls T esttnt Sh••t : A4 of :S SB 3 2-12-91 Surfaot ORGANICS, Brown, Froztn, (w /Sticks or W'ood Dtbr;s) Snty SAND, Ql;ve, Froztn, Sindy GRAVEL w/Sm. SHt, OHvt, (Pt) (SM) Froztn, (Rooks to!"), (GM) (!)78 Sindy GRAVEL .., /Tr. snt I 011vt I Ss V. Dtns:t, Moist, (GP-GM) B.O' 'w'~t•r@ 1 0.5' 'w' .0. (Cobblts or Coirst Gravel W'.D.) @38 SAND w /Sm. Or an 1, OHvt, Dtnn, W'tt, (SP) T.D. SB 3 & SB 4 SB 4 2-12-91 Sandy GRAVEL w/Sm. SHt, OHvt, DtnSt, Froztn or Moist, (GM) (Cobblts to 4" 1n iUQtr rtturn) (!)34 Sindy OR AVEL .., /Tr. snt I 011vt I Dtns:t, Sl. Moist, (OP-OM) ® 49 Sandy OR AVEL w /Tr. Silt, Olivt, Dtnst, W'tt, (OP-OM) W'attr ~ 11 .5' W' .D. @68 Sand!J GRAVEL w/Tr. to Sm. SHt, 011vt , V. Dtnst, W'tt, (OM) T.o.· Norlltern lest Lab Ana 1y tic a 1., EnYironm•nta 1., G•ot•chnica 1., Construotton Materials T•sting so 5 2-12-91 Surfact ORGANICS 1 Brown 1 Frcztn 1 ( w /Sticks or Wood ow;s) SandiJ GRAVEL w/Sm. Snt1 OHvt 1 Dtnst 1 Froztn or Moist 1 G) 11 (Pt) (GM) Soil Boring Log Oat•: 2-24-91 Initials: A.T. AEA Dave·s Creek Seal•: 1" = 3.0' Geotechnica 1 lnYutigation Sheet : A:S of :1 so 5 & so 6 so 6 2-12-91 2.0' G Surface Or'jlanics 1 Brown 1 Frozen 1 (Pt) Sandv GRAVEL w/Sm. Snt 1 01iVt 1 Dtnst1 Froztn or Moist1 (GM) (Cobblts to 4" in Au'jltr Rtturn) (!)64 SandiJ GRAVEL w /Tr. Silt 1 Olivt 1 V. Dtnst 1 Sl. Moist 1 (GP-GM) SAND w /Sm. OrQanto Silt 1 Oltvt (sand) IT an (silt) 1 Loost/Soft 1 Moist1 (SP/Ml) (Coarse Gravtl or Cobbles W.O.) 042 S1nd1J GRAYEL w/Tr. to No Silt1 Dtnse 1 Wtt 1 (GP-GM) W attr @ 11.0 "w' .D. (Cobblts or Coarse Gravel W.O.) (!)a6 SAND w /Sm. Gr avt 11 OHvt 1 V .Dtnst 1 S.nd\j GR AYEL w /Tr. to No sm I Wtt1 (SP) T.D. Olin • V. Dtnse I Wtt, (GP) r.o .· :lett' 2/22/91 I Project No.' 91019 PrO)tCI• Daves Creek Subdivision Atttntlon • tl6r ltiltAiiLASKi i!iit ~[846 Materials and Quality Control Testing Architect /En9in11r • Contractor • BILLING/ RESULTS TO: Copy• Alaska Energy Authority P.O. Box 190869 Pooe .#B1 .~chorage, Alaska 99519-0689 SUMMARY SHEET c:i Lab# Q?~i Q?RT Q?RT Q?~T ....: Date 2/11/91 2/11/91 2/11/91 2/11/91 UJ 1111 r.r~mhi nPri A C,omhi necl R TH!.J.. ...J a.. S::~lTinl P 1 S::~nmlP ? Samnle ,qs SAmnle 1 ~ <t 'Jnrf>ri (/) . 3" 2" 11/2" 100 100 I" 100 92 89 100 I I 3/4" 90 81 86 91 1/2" 85 63 75 80 I I I (!) 3/8" 78 57 67 76 I z iii #4 53 42 so 60 (/) I ~ #10 31 27 35 42 I I ..... #20 17 17 ' 24 27 I I z I w #40 12 ll 17 17 I (.) I a:: #100 5 7 11 9 : i w : I a.. 3.2 ts.J I #200 5.2 ! 6.1 i .02mm .05 mm I i I 002mm ! I ! YOISTUR>:: ! i • _,QUID UMIT i I i : ;JLASTIC tNDEX i I I SPECIFIC GRAVITY i i : i :o/o FRACTURE -t-#4 ! I l : JSC CLASS C:P r:P-f:\-1 i GP---G.'-1 . GP-G\1 : :);o BITUMINOUS ! i r:ROST CLASS i i I ' MAXIMUM DENSITY ! ! ADJ. LAB DENSITY I i : :PT!MUM MOISTURE I ! i ZES NOT CONFORM I : 1,2; 1H l, Sc.j_~le ·). TH ?)!' Scl!-;::Jle 1. ' 0 If) - 140' 200' ----------170' ------------! 0 SB-1 <100.0> AEA SITE r1s· r----0 SB-6 (97.8) -------120' ---+-------i r-------+-60' ---......f .-------+-------0 SB-5 (97.5) 140' r-0 sB-3 1 <97.7> DRIVE 25' ~D NORTH 30 60 I NORTHEAST END OF EXISTING C.E.A. SUB. EXISTING FENCE 0 SB-3 (97.7) DRA \.liNG 'C' -SOIL BORING w/ RELATIVE ELEVATION ALASKA ENERGY AUTHORITY DAVES CREEK GEOTECHNICAL APPROX. SOIL BORING LOCATIONS fEB. 1'391 AEA PREPARED BY Northern lett Lcm I ·I Norlltern lest Lab An~ 1y ttca 1, Envtronm•nb I, G•ot•chnica 1, Construction Hater'ia ls T •stinCJ •NON-BEARING WAl.L-6" MIN. _ BEARING WALL -A5 ~E:QUI~ED, · · 12.'' MIN •. AEA 5UbSt8t1on D~t•: 11-28-90 G•ot•chnic~l lnv•sttCJ~tion lniti~ls: A. T. Shellow Footing Details Seal•: NTS Drawing: D ~ "'tJG.. s ~ P; ..J; wxf.,-to~ 10 .,J.,J,::. w -. z• ~~o · f'OL.',c;;rr~N€ -=n,r:;,tJL}rlot-.1.. 5HALLD\A/ GONVEblTIONAL FCVTI~s ~T~