Loading...
HomeMy WebLinkAboutCHUGIAK SCHOOL Geotech InvestigationGEOTECHNICAL INVESTIGATION AND FOUNDATION RECOMMENDATIONS FOR ADDITION TO CHUGIAK HIGH SCHOOL PREPARED FOR TRA/FARR ARCHITECTS & PLANNERS BY ~Engineers MAY 1985 DOWL Engineers 4040 "B" Street Anchorage, Alaska 99503 Telephone (907) 562-2000 May 23, 1985 W. 0 · #O 5 1 6 8 0 MUNICIPALITY OF ANCHORAOE DEPT. OF HEALTH & ENVIRONMENTAL PROTECTION lRA/Farr Architects and Planners 1001 East Benson Blvd. Anchorage, Alaska 99508 JUL © 1986 RECEI EQ Attention: Dan Fair Subject: Geotechnical Investiqation and Foundation Recommendations for the Addition to Chugiak High School Gentlemen: lransmitted herein are the results of the geotechnical investiga- tion for additions and site improvements at Chugiak High School. lhe report also gives recommendations for foundation design and discuss subsurface conditions which may impact the design and construction. Included in the report are thirty test borinq lags, electromagnetic resistivity survey results and results of the laboratory and field testing. ]he recommendations presented in this report reflect our current understanding of the planned development and the nature of the subsurf.ace soils at the site. Should it become apparent during construction that subsurface soil conditions differ from those encountered during our investigation or if your development plans change, we should be contacted promptly to evaluate our recommen- dations with regard to those changes. It is particularly impor- tant that the building location not be moved more than five feet feet without giving us an opportunity to review the impact that might bare on our recommendations. If you have any questions regarding this report or if we may be or further assistance, please feel free to call. Approved: Melvin R. ic els, ~artner GC:MRN:kF Attachments Sincerely, BOWL ENGINEERS Geotechnical Engineer GEOIECHNICAL INVESIIGAIION AND FOUNDATION RECOMMENDATIONS FOR THE CHUGIAK HIGH SCHOOL ADDITION TRA/FARR P~epared for: ARCHIiECIS And PLANNERS Prepared by: DOWL ENGINEERS 4040 "B" STREET ANCHORAGE, ALASKA 9950] W.O. #D51680 May, 1985 TABLE OF CONIENIS PAGE INTRODUCTION .............. 1 Previous Investigations ........................... 3 SITE CONDIIIONS ...... Surface ............ Subsurface ......... Field Soil lesting. Groundwater ........ Permafrost ......... 4 4 4 6 6 7 LABORATORY SOILS TESTING ............................ 7 CONCLUSIONS AND RECOMMENDATIONS ..................... Foundations ........ Frost Protection... Earthwork .......... Soil Slopes .......... Sheet Pile Wall ...... Paved Areas .......... Athletic Facilities... Site Drainage ......... Inspection ............ 9 9 10. 12 14 17 18 19 19 FIELD EXPLORAIION AND LABORATORY TESIING ............ 20 ELECTROMAGNEIIC RESISTIVITY SURVEY .................. 22 LIST OF FIGURES Test Boring Location Map ............................ Figure 1 Test Boring Logs .................................... Figures 2-31 Grain Size Distribution Curves ...................... Figures 32-38 Grain Size lriaxial Compression Samples ........... Figures 39-40 lriaxial Compression lest Results ................... Figures 41-48 Stress Distribution Against Sheet Pile Retaining Structure ............................... Figure 49 EM-31 Resistivity Map ............................... Figure 50 Standard Explanatory Information .................... Sheets 1-3 Appendix A Previous Test Borings (1984) GE01£CHNICAL INVESIIGAIION AND RECOMMENDAIIONS FOR THE CHUGIAK HIGH SCHOOL ADDIIIuN INIRODUCTION lhis report presents the results off the geotechnical investiga- tion conducted for TRA/Farr Architects and Planners at the exist- ing Chugiak High School in the areas of the proposed additions and site modification. The site is located adjacent to the Glenn Highway north of Eagle River, Alaska. The site is within Sec- tions 19 and 30 of lownship 15N, Range 1W, Seward Meridian, Alaska. lhe purpose of this investigation was to define the subsurface conditions at the site including the presence of the groundwater table, any unsuitable soils, and the suitability of the site for on-site sewage disoposal, lhis information was used to make rec- ommendations regarding the foundation design, the protection of the bearing soils of the existing structure during construction and the development of the site. lhe first phase of the site investigation consisted of an elec- tromagnetic resistivity survey (EM-31) of the ares at the south end of the existing structure, lhis EM-31 survey was performed to try to locate a septic system which was thought to exist in the area. lhe survey was conducted on a 25 foot grid and indicated several anomalies which could then be avoided during drilling. A description of this survey is contained at the end of this report. Later during the drilling program, the EM-31 was again taken to the site to try to locate the waterline entering the existing school from the well to the north, lhis effort proved to be unsuccessful due to the other utilities entering the building at the same general location and other metallic features in the gen- eral area. During the subsurface investigation, a total of thirty test bor- ings were drilled. Ten test borings were drilled to a depth of about 30 feet, four test borings were drilled to a depth of about 20 feet, and fourteen test borings were drilled to a depth of 10 feet. The remaining two holes were drilled to a depth of 15 feet and.a percolation test was performed at the location of these two borings. It should be noted that three of the originally located test bor- ings were. not drilled because of interference with existing utilities or the fear of drilling into utilities which could not be located but were known to exist, lwo additional test borings were drilled at the southern limits of the proposed addition to further define the soil conditions in this area and determine if the septic system did exist in that area. ]he test borings were located both horizontally and vertically by standard survey techniques (DOWL Field Book No. 925). Ihe test boring locations are shown on Figure I, Test Boring Location Map. Soil samples obtained during the field investigation were visual- ly classified both in the field and in the laboratory. Moisture content tests were performed on most of the samples, and selected samples were identified for further laboratory testing. This included samples for sieve analysis, hydrometer analysis, and Atterberg limits testing. In addition to the testing for classi- fication, a total of six consolidated, drained triaxial compres- sion tests were performed to evaluate some of the engineering characteristics of the soils. Planned Construction west side with a addition will have two stories above school structure, The current design concept indicates the existing Chugiak High School will have an addition constructed on the south and south- plan area of about 50,000 square feet. Ihe a basement under a portion of it and one or grade. On the north side of the existing a single-story addition of about 8,ZOO square feet will be constructed, lhe transformer room located on the south side of the existing structure will be increased in size and a glass-enclosed walkway is to be constructed in the existing courtyard. addition to the building additions, there are many new facili- ties planned for the school grounds, lhese two hockey rinks, a soccer/football field, field, two tennis courts, three new parking modifications to existing facilities. facilities include a soccer/baseball areas, and other P~evious Znves[i~ations A subsurface investigation was performed by Attic Alaska Testing Laboratory in Hay of 1963. Ihis investigation included forty- three test borings which were distributed across the site. It is not known how these test borings were located nor is it known how the borings were sampled, ]he boring logs which are on a drawing by Edwin Crittenden-Architecte indicate that the site was covered with a layer of organics and silt of from 2 to 4 feet in thick- ness. Beneath the silts is a thick layer of sandy gravel with boulders. In some locations there is some silt in the gravel. It should be noted that since 1963 therff has been extensive grad- ing at the site and the soil conditions indicated on the test borings from 1963 may not apply in many areas of the site. ]wo more recent borings were located within the general area. These two borings were located in the northwest area of the site and were drilled in 1984 as part of the P-2 segment of the pipe- line for the £klutna Water Project. ]hese test borings indicated organic fill to a maximum depth of 13 feet. lhese test borings are shown on the lest Boring Location Map, Figure 1, and the test boring logs are included in Appendix A of this report. SIIE CONDIIIONS Surface lhe topography of Chugiak High School is relatively flat. On the south and southwest side of the existing school structure there are presently several temporary classroom units, lhere are many overhead and subsurface utilities around the school that inter- fered with the exploration process. The remainder of the site is covered with parking, athletic fields, and other school facili- ties. Much of the site is paved or grass covered with small por- tions of the site being brush covered or wooded. Subsurface lhe soils at the site consist of a thin layer of silt over a poorly graded gravel. At some locations at the site the silt is not present, but where it is present, it classifies as a sandy silt or silty sand. The northwest area of the site has had a poor fill material with organics placed to depths as great as feet. Apparently a natural hole was filled in with waste mate- rial. lhere are other isolated areas of the site where fill from past grading was detected, lhe soils at the site are described in detail below and on the test boring logs, Figures 2 through 31. To help understand the information presented on the boring logs, please refer to the standard explanatory information con- tained on Sheets 1 through 3. Fill: lhe test borings indicate that there are isolated areas of fill at the site from past grading, lhe fill present in the northwest area of the site has a thickness of at least 13 feet. This fill material is soft and generally high in organic and silt content, lhis fill material is generally highly compressible and unsuitable as a bearing material. Silty Sand and Sandy Silt: At the surface or directly beneath the fill at the site there is a layer of sandy silt or silty sand which is generally less than 3 feet in thickness. This stratum ia not present over the entire site; it may have been removed durinq past grading at the site. These soils are generally very frost susceptible. G~avels: Ihe soils at a depth of 3 feet or more at the site (excluding the fill areas) consist exclusively of relatively clean gravels with a few areas of sand. In general, the gravels have a silt content of about 5 percent and are free-draining, dry, and very dense. There are occasional areas of cobbles and boulders within this gravel stratum. Special Conditions: It was anticipated that some of the test borings at the south end of the school might interc, ept the septic system which was known to exist in that general area. ]he only bori~]g which intercepted the system was Test Boring )2A which intercepted the septic material at a depth of 18.5 feet. It was impossible to determine if the system was still in use from the data obtained. Field Soil Testing During the geotechnical investigation, two percolation tests were performed at the site within the gravel layer directly beneath the surfsce sandy silt or silty sand stratum, lhese tests were performed in augered holes immediately adjacent to lest Boring 16 and lest Boring 17. The test performed adjacent to ]est Boring 16 indicated a percolation rate of I minute per inch, and the test perormed adjacent to Test Bering 17 indicated a percolation rate of less than 1 minute per inch. ~oundwateT The groundwater was detected in only four test borings during drilling. These test borings were all located at the south end of the existing school, lhe depth st which the groundwater was detected was from 8 to 23 feet within these four test hole's. It should be noted that the groundwater level determined during drilling is very subjective and may not give a good representa- tion of the true groundwater conditions. RVC standpipes were installed in about half of the test borings. ]he depth to the water level in these standpipes was measured on April 4, 5, and 10, 1985, and no groundwater was observed in any of the standpipes. These results are indicated on each boring log. From these water level measurements it can be concluded that the water table is below the limits of excavation, and therefore, should not present a problem during construction. The groundwater table should be expected to experience seasonal fluctuations and can be expected to be at or near a seasonal low at the time the soils exploration was performed, However, only minor construction dewatering during site preparation and footing construction may be required, Permafrost During the soils investigation, no permafrost was observed in any of the test borings at the site. lhe risk of permafrost existing undetected within the building area is very remote. LABORAIORY SOILS IESIENG AfEer the soil samples obtained in the field were transported to the laboratory, they were again visually classified, the natural moisture contents were obtained, and samples were selected for further laboratory testing, Grain Size Distribution: Seven samples were selected for sieve analyses and five of the samples also had hydrometer analyses performed on them for the determination of frost classification. lhe results of these laboratory tests are summarized 'below and are presented in graphical Form in Figures 32 through 38. GRAIN SIZE DISIRIBUIION lest Boring Sample!% Gravell% Sand % Silt % Clay Size Size Size Size 17 I 27 30 12 31 18 1 2 22 - - 20 3 O 52 - - 21 1 49 39 4 8 22 1 ~1 ~2 8 9 23 2 0 ? - - 31 3 39 35 8 18 Atterberg Limits: Two samples of near-surface soil were selected for determination of Atterberg limits. .The sample from a depth of 2.5 feet in Test Boring 23 had a Liquid Limit of 47 and a Plasticity Index of 11. lhe sample taken at the ground surface in lest Bo~ing 18 had a Liquid Limit of~36 and e Plasticity Index of 7. Consolidated-Drsine4 ]riaxial Compression: A total of six con- solidated-drained triaxial compression tests were perofrmed on soils recovered from the site. One series of three tests was performed on the g~avel from about 10 feet within the building footprint area. These soil tests were performed on samples from lest BoFing 5. The purpose of this testing was to define the strength characteristics of the soil that will be the bearing material. ]he other series of three triaxial tests was performed on the soil in the area of lest Boring 7 between the depths of 1 to 8 feet. lhe purpose of this testing was to define the engi- neering characteristics of the soil that must be restrained with a retaining structure during the excavation of the basement area. The triaxial tests were performed on 4-inch diameter specimens of the recompacted soil. The soil samples were passed over a sieve and all material larger than 3/4-inch was removed. The gradation of each sample is shown graphically in Figures 39 and 40. The specimens were compacted to a dry density off 125 pounds per cubic foot. Ihis density is believed to be a reasonable approxi- mation of the insitu condition. The results of the triaxial testing are presented graphically in Figures 41 through 48. From these figures it can be seen that the effective angle of internal friction for the gravels tested is between 39 and 45 degrees. CONCLUSIONS AND RECONMENDAIIONS Foundations lhe planned additions can be supported on conventional spread footings founded on the gravels found directly beneath the sur- face organics and silt or on structural fill material as speci- fied below, lhe spread footings may be designed for an allowable soil bearing pressure of 4000 pounds per square foot for dead loads and long-term live loads. The glass enclosed walkway in the courtyard should be designed for an allowable soil bearing pressure of 3000 pounds per square foot because off the lack o~ information about the soil conditions in this area. If du~ing construction in this area any unexpected subsurface conditions are encountered,-, we should be contacted to evaluate the situa- tion. The allowable soil bearing pressure may be increased by one-third when considering short-term wind and seismic loads. The allowable soil bearing pressure is predicated on the founda- tion soils and structural fills within the building area remain- ing thawed throughout the construction period and over the life- time of the building. 9 the minimum width of continuous footings should be 18 inches. ' Rerimeter footings should be founded at least 42 inches below the adjscent grade. All interior footings should be founded at least · 24 inches below the lowest adjacent grade unless constrained by a slab on grade. The anticipated settlement of the structure will be minimal because of the very dense nature of the gravels. ]he settlement will be less than one inch total and differential settlements of 1/2 inch or less may be anticipated. This opinion is based on the assumption that the recommendations of this report, particu- larly those covering earthwork, are carefully roi. lowed. For design of the foundation for earthquake loadings, a .coeffi- cient of sliding friction between the footing and the soil of 0.75 may be used. In conjunction with this frictional resist- ance, the passive resistance of the soil is equal to that for static loading (525 psf/ft equivalent fluid pressure). For the design of szgns and light poles to resist wind loads, a passive soil resistance of 525 pounds per square foot per foot of depth equivalent fluid pressure may be used. It is recommended that these sign posts be analyzed as if they were short, stiff, laterally loaded piles. All posts should be embedded a minimum of three feet. It should be recognized that this technique for determining required embedment does not consider frost jacking of the posts, lo pre. vent frost jacking of the posts will require a much greater embed~ent length. FrosL Protection Heated perimeter footings should be founded at least 42 inches below exterior finish grade. Ne also recommend a 2-inch thick 10 layer of non-water absorbing, closed-cell, extruded polystyrene insulation be installed below grade on the outboard Face of exterior Footing walls for frost protection of heated Footings. Where the foundation wall extends above the exterior Finish grade, that portion of the insulation may be placed on the inboard Face of the wall and lapped at least 12 inches beyond the exterior insulation. Furthermore, we recommend that the floor remain uninsulated. This approach to foundation serves two purposes: 1) to provide a frost bond break to prevent uplift the side of the Footing walls, and 2) insulation to allow waste building heat to flow downward below footings and keep the bearing soils thawed. Other insulation schemes msy also be adequate and acceptable. this is only one example of an appropriate method. If during construction, the buildings will not be heated before winter, a system must be employed to prevent the foundation soils and the structural fill within the building areas From Freezing and adversely affecting the buildings and the structural fill. If the Foundation soils are not kept heated, t~mperature instru- mentation should be installed at several locations in the founda- tion soils, and monitored throughout the winter. Also, a system of survey benchmarks on the at-grade interior slab should be mon- itored to detect possible frost heave within the building during that period. Careful monitoring of soil temperatures and Footing movements will allow for minimizing the amount of construction heating or foundation replacement required. 11 Earthwork Earthwork at this site must consist of removal of all organic material and silts in the ares of the proposed additions. Special effort will be required to ensure that all loose backfill along existing utilities is removed and replaced with structural fill. lhis will be of special concern in the ares of the old septic field in the general area of lest Boring 32A. During the excavation within the building area and also during any periods of dewatering (if necessary) care must be exercised to ensure that the adjacent structure is not adversely impacted. One scheme to protect the existing structure during excavation is discussed later in this report. During excavation, any subsoil which is disturbed should be redensified, if possible, or com- pletely removed. Do not place fill or construct foundations over disturbed or frozen soil. Structural fill which is used to replace material removed from the site should consist of non-frost susceptible (NFS) sandy gravel meeting the following gradation requirements for the minus 3-inch: Sieve Size Percent Finer By Weight 3" 100' 3/4" 30 100 1/2" 25 - 100 #4 20 49 #40 0 - 25 #200 0 6 0.02 mm 0 - 3 *1he fill may contain up to 107~ cobbles. 12 Some NFS fill material which does not meet this gradation requirement may be acceptable for use. However, the gradation of any such material should be evaluated by a geotechnical engineer to assess its suitability as fill material prior to its use. Structural fill should be placed and compacted in lifts not exceeding 12 inches in thickness if a large vibratory compactor is used, or not exceeding 6 inches in thickness if a hand operated compactor is used. Each lift of structural fill should be compacted throughout its entire depth to a density of at least 95 percent of the maximum index density determined in accordance with ASTH D4253. In-place density tests should be performed on each lift of fill to verify the fill has been properly compacted prior to placing overlying lifts. Rroperly compacted structural fill should extend laterally from the edge of footings and slabs a minimum of 1 foot for.each foot of fill beneath the footing or slab. Soil Slopes Any slopes at the site created on a temporary basis for the put- pose of construction should be at 1. If temporary slopes are at a 1 that some areas of sloughing and areas will require remedial work. a slope no steeper than 1 to to 1, it must be anticipated raveling will occur and these It is especialy important that the slopes are at least 1 to 1 or flatter when working near the existing structure. Any permanent slopes should be no steeper than 2 horizontal to 1 vertical. If at all possible, flatter slopes should be used since this will lessen the problems of 13 erosion, lhe permanent slopes may require some type of temporary erosion protection until vegetation can be established. In all cases, all Stats of Alaska, Municipality of Anchorage, and OSHA regulations regarding temporary utility trenches and excavations should be rigidly followed. Sheet Pile Wail Most' of the excavated area for the basement under the building addition is to be far enough away from the existing structure to prevent any adverse impact on the existing footings and their bearing soils, lhe one area off the existing structure that must be protected is the protrusion along the southwest wall of the school in the general area between Test 8oring 7 and Test Boring 8, as well as some other areas. To protect the integrity of the existing bearing soil and foot- ings in these areas, a sheet pile wall with tie bscks may be used. A diagram of the stresses that will be acting on this wall is shown in Figure 49. It has beeo assumed that the stress applied by the footings is a surcharge type loading of 3,000 pounds per square foot rather thsn a line load. This assumption is made because the applied footing loads and width of the exist- ing footings are unknown. It should be recognized that this wall should be designed to prevent as much lateral movement of the bearing soils as possible. Should the lateral movement of the sheet pile wall not be restricted enough, it will result in set- tlements and possible damage to the existing facility. Although the applied stresses could possibly be resisted by the bending moment in the sheet pile sections, it is our opinion that the design will be more effective if a whale is used across the top of the sheet pile wall and rock bolts are used to tie the top of the sheet pile wall back to the existing structure, lhe load- ing applied to the existing footings by the rock bolts will be resisted by the slidiog function between the .footing and the bearing soil. After the sheet piles are installed, localized excavations may be allowed to facilitate the installation of the rock bolts and whales but the extent of the excavation should be kept to. a mini- mum until after all the tie-backs are installed. It should be noted that the installation of some of the sheet piles may pre- sent some problems due to the dense nature of the gravels at the site and the occasional cobbles and boulders in the gravel. lhe installation of the sheet pile wall and the associated tie- backs will be critical to the successful excavation near the existing structure. It cannot be over-emphasized that an inade- quate or improperly installed tie-back wall could result in irreversible damage to the existing school. Another method that may be used to protect the existing structure is the use of soldier piles and lagginq, lhis may present lass construction problems than the sheet pile wall since any existing cobbles or boulders will not present a problem. 1he soldier piles should be placed in drilled and cased holes to a sufficient depth that 'the bending in the soldier pile will be limited to 1/4 inch of lateral movement or less. 7he soldier piles should be grouted into the drilled hole with 8 lean grout or lean concrete mix. Ihe casing may be left in place or removed, with removal being preferable. For design of the soldier piles, the same stress distribution as is shown in Figure 15 49 will apply with the exception that an equivalent fluid pres- sure of 32 pounds per square foot per foot of depth should be used as the pressure against the lagging, lhis pressure is only to be used for sizing the lagging. As the excavation proceeds, the lagging boards should be installed prior to excavating more than a depth equal to the width of the lagging board plus three inches. Between each set of lagging, spaces of about one inch thickness should be installed. This will allow backpacking to be inserted into the space between lagging rows and the fillinq of the void between the lagging board and the excavated soil face. Sand or a grout mix may be used for the backpacking material. It is imperative that this backpacking operation be properly and completely per- formed as the excavation proceeds if settlements of the existing structure are to be minimized. The final recommendation regarding the protection of the existing school during all excavation below the footing level is that a monitoring program be established which will give a warning if the existing structure starts to move due to the excavation process. This could be implemented in several ways. One method would be by survey techniques and another is with instruments measuring the building movements relative to some deep seated benchmarks. If the total downward movement of the existing structure exceeds one-quarter inch, a minimum of 5 feet of fill should be placed against the excavated side of the wall. All excavation should stop and we should be notified promptly to evaluate the situation. lhe design of a building monitoring program is outside the scope of work of our study but could be performed at a later date. 16 Paved Areas In the proposed parking areas and areas of rerouted streets, the topsoil and silt should be removed, lhe area may then be raised using NFS granular fill meeting the structural fill require- ments. ]he pavement section should satisfy the Corp of Engineers requirements for thaw stability. ]he Municipality of Anchorage uses the followinq guidelines for minimum depths of subbase on residential streets. Ihicker sections are required for heavier loadings. Subgrade Frost Classification NFS Fill Required NFS 0 F1 1.5' F2 1.7' F3 2.3' F4 3.3' For moderate traffic loads, a base course thickness of 2 inches and an asphaltic concrete thickness of 2 inches should be adequate. A base course meeting the State of Alaska, Department of lransportation and Public Facilities D-1 Specifications, and an asphaltic concrete such as Class C, Municipality off Anchorage mix or Class II, State of Alaska mix, are commonly used, but others are acceptable. All structural fill should be constructed in lifts no more than 1 foot thick, compacted to the specified density, and tested as previously discussed. 17 Athletic Facilities lhe proposed new athletic facilities at the site are of special interest, lhe hockey rinks and tennis courts must be treated in a similar manner to the parking facilities. This is necessary because of the problems with the rinks and tennis courts if large differential settlements occur due to underlying soil conditions or frost action. lhe new athletic field east of the existing school should present few geotechnical problems if the organic, near-surface soils are replaced with NFS fill and the field is developed with good drainage. The new athletic field northwest of the existing school structure will present some problems, lhis area of the site has had extensive filling and grading performed in the past. Some of the test borings indicate as much as 13 feet of poor fill material containing peat and wood. lhe fill is soft as indicated by the low blow counts (N values) obtained during the sampling process. There are basically two approaches that might be taken to develop the northwest athletic field, lhe first method would be to remove all the poor fill and replace it with a properly compacted fill section prior to development of the field, lhe second tech- nique would be to grade off the area, place a geotextile above the existing soil and construct a properly placed fill section resulting in a raised field. If this second option is usedi the owner must be aware that settlement problems will occur with time and these problems will require regular site grading in the athletic field area possibly as often as yearly, lhe owner must be willing to accept the extra maintenance problems should the second option be utilized. 18 Site Drainage The finished grade at the site should be such that all surface and roof runoff is quickly drained away from the area of the structure. This will help prevent water-induced foundation prob- lems. In the area of the rest of the facilities, the surface water should also be drained rapidly away from the area. Inspection It is critical to the adequate performance of the planned struc- tures and facilities that all organic soils be completely removed where specified and that all structural fill consists of proper materials and is adequately compacted. Therefore, we recommend all excavation and backfill be continuously observed by qualified inspection/testing personnel, and that frequent in-place density tests be performed to verify that minimum fill quality and dens- ity are attained. In addition we recommend that a qualified and experienced repre- sentative of the owner constantly monitor the performance of the existing structure while all excavation adjacent to and below the footing elevation is performed. It is critical to the integrity of the existing school that the bearing soils beneath the foot- ings not be disturbed. ]he degree of precision necessary durinq the monitoring of the existing structures is very demanding. It will require monitoring vertical building movements to a minimum of the nearest O.01-inch and it would be even more desirable to monitor the vertical movements to the nearest O.OOl-inch. 19 FIELD EXPLORAIION AND LABORAIORY lESlING lhe subsurface investigation for the planned Chugiak High School Addition and Facilities Improvements was conducted on March 22 to April 5, 1985. lhirty test borings were drilled to depths of 10 to 30 feet below existing grade within the general site area. lhese test borings were located by standard survey technique (DOWL Field Book No. 925). lhe boring locations are shown on the Test Boring Location Map, Figure 1. Prior to drilling, an electromagnetic resistivity survey (EM-31) was performed at the south end of the existing school building. Ibis information was then used in locatfng the test borings in the area. Some test borings were drilled with a Mobile B-61 truck-mounted drill rig, and some were drilled with a Nodwell mounted B-61. Both were fitted with continuous flight, hollow stem auger. The drill rigs are owned and operated by Denali Drilling, Inc. lhe field investigation was directed and the test borings logged by Carol Klein, geologist with Alaska Testlab. lhe standard penetration test (SR1) was performed and disturbed samples obtained in each boring at 2.5 foot to 5.0 foot intervals, lhe SRl is an indication of the relative density or consistency'of the subsoils, fhe SRl was performed by driving a' 2-inch O.D. split spoon sampler a distance of 18 inches ahead of the auger with a 140-pound hammer falling 30 inches in accordance with ASIM D1586. lhe standard penetration resistance (N) value shown on the test boring logs is the number of blows required to drive the sampler the last 12 inches. Some samples were obtained by driving a 2.5-inch I.D. split spoon sampler with a 340-pound weight free falling 30 inches, lhe different sample types are shown graphically on the test boring logs. 2O Samples recovered from the borings were visually classified and sealed in plastic bags to preserve the natural water content. In the laboratory, each sample was again visually classified by an engineering technician and the natural water content of most of the samples was measured. Additional laboratory testing was per- formed on selected samples to determine particle-size distribu- tions, frost classification, and Atterberg limits, lwo sets of three consolidated-drained triaxial compression tests were also performed to help define the engineering characteristics of the soil. Ail tests were performed in accordance with applicsble ASlM standards. 21 ELECIROMAGNEIIC RESISIIVIIY SURVEY Prior to the initiation of the test boring program, an electro- .magnetic resistivity survey was conduct'ed over a portion of the buildinq footprint, southwest of the existing structure (see Figure 1). The primary purpose of the survey was to help locate a septic system that was reportedly buried in this area. lhe resistivity survey wes conducted using a Geonics EM-31 )errsin Conductivity Meter.' lhis instrument measures the apparent con- ductivity of the ground to a depth of approximately 20 feet by utilizing the principles of magnetic induction. lhe EM-31 survey was conducted on March 22, 1985 by Carol Klein, geologist, and Steve Smith, geophysicist, with Alaska ]estlab. A 20-foot by 20-foot grid was established on the site by means of cloth tape and right angle prism, using the southwest wall of the high school as a base line. lhe southwest corner of the building was assigned the coordinates 1000N, IO00E. Other stations are referenced to this point. Because of the temporary buildings along the edge of the school, the actual survey began 50 feet southwest of the base line, along grid line 950N (see Fig- ute 50). Readings were taken and recorded at 20-foot intervals within the grid. lhe meter dial was also monitored between sta- tion readings in order to detect anomalous behavior. An area of approximately 260 feet by 220 feet was covered by the survey. lhe terrain conductivity readings at per meter) were converted to apparent meters) and are presented as a contour each station (in millimhos resistivity values (in ohm- map of apparent resistivi- ty in Figure 50. 22 lhe resistivity map reveals some distinct anomalies on an other- wise "flat" background, lhe site was covered by snow at the time of the survey; therefore, it was not possible to see debris that may have been lyinq on the ground. Pieces of metal, concrete, and other manmade items can produce noticeable EM anomalies that may appear as localized highs or lows on the contour map. site was covered by snow at the time of the survey; therefore, it was not possible to see debris that may have been lying on the ground. Pieces of metal, concrete, and other manmade items can produce noticeable EM anomalies that may appear as localized highs or lows on the contour map. lhe elongate resistivity low along the north edge of the grid is caused by a buried gas line. Alo.ng the southern edge, low values are related to a nearby metallic fence. A circular "high" at Station 910N, 1020E appears to be a one-point anomaly that was probably produced by debris on or near the ground surface. A somewhat larqer anomaly, centered roughly on Sbation 890N, 1180E, involves several points on the grid and appears to be due to a more substantial object at a relatively shallow depth beneath the surface. ]he EM-31's normal penetration of approxi- mately 20 feet can be cut in half by tilting thC instrument side- ways, and even with this configuration, the anomaly was detected in the Field. This suggests that the object may be within 10 feet of the surface. A buried metallic tank would be capable of producing this type of anomaly. Coincidentally, the original staked location of Test Boring 2 was practically in bhe center of the anomaly. In order to avoid drilling into a possible septic tank, the test hole was offset to bhe west by 10 Feet. The mate- rials encountered in lest Boring 2 were in no way unusual or atypical of the site in general. Another pronounced anomaly is evident at Station 810N, 1120E. This appears to be another one-point feature such as the one at Stabion 910N, 1020E, and a localized concentration of debris would again be suggested. Two test borings (72 and 32A) were drilled near this anomaly. As described elsewhere in this report, Test Boring 32 encountered auger refusal at a depth approximately 17 feet, while Test Boring ~2A 'intersected satu- rated, odoriferous soils at 17 feet. Since this depth is near the normal detection limit of the EM-31, it is not very likely that the materials at 17 feet produced the strong resistivity high seen on the contour map. Its proximity to the unusual soil conditions may be coincidental. Aside from the anomalies discussed above, the site appears fairly uniform in terms of resistivity. The EM-~I survey alone did not clearly define a buried septic system. In conjunction with the test boring data (especially T8 32A), there is a possibility that a relatively deep wastewater plume exists under part of the site, possibly issuing from a tank buried near Station 890N, 1180E. 0 5 I T=46 L 15 ½ 3 T=44 o_~20 ~ i3 T=46 F L 35 L_ lNG 1 TEST BOR LOCATiON=SEE TEST BORING LOCATION MAP ELEVATION= 276.0 FiLL.NF$~ DARK BROWN SANDY GRAVEL WiTH ABOUT 5% SILT. ANGULAR TO SUBANGULAR GRAVEL TO 3", FROZEN NFS, BROWN SANDY GRAVEL WiTH LESS THAN 5% SILT, SOME SCATTERED COBBLES. GRAVEL TO 3". DAMP TO WET. VERY DENSE GROUNDWATER LEVEL WHILE DRILLING ri2.0 FT) TEST BORING COMPLETED 3/26/85 PVC STANDPIPE INSTALLED NO WATER IN STANDPIPE ON 4/N/05 OR q/10/85 DEPTH 3.5 29.7 KEY MA = MECHANICAL ANALYSIS LL = LiQUiD LIMIT ~l = PLASTIC INDEX pP = POCKET PENETROMETER rTSF~ TV = TORVANE (TSF~ [] = GRAB SAMPLE [] = SPT SAMPLE ~ = SHELBY TdBE-PUSHEO ~ = 2.5" i.O- SPOON SAMPLE 3~0# WEIGHT. 30" mALL T = SAMPLE.TFMPERATORE (JF) PROBABLY AFFECTED BY SAMPLING PROCEDURE DOWL ENGINEERS LOG OF BORING LOGGED BY CAROL KLEIN W.9. D5i680 FIGURE 2 0 5 ~0 iS :z:2D 25 30 35 ? L F r3 j6 j7 T=45 T=47 T=46 TEST BORING 2 zo LOCATiON=SEE TEST BORING LOCATION MAP v u. ELEVATION= 276.0 DEPTH ~.~F2/F4, DARK BROWN SILTY SAND, FROZEN Fl, DARK BROWN SILTY SANDY ANGULAR GRACEL TO 3", FROZEN 1.0 3-5 F2, DARK BROWN SAND WITH SOME SILT. SOME ANGULAR GRAVEL TO 1/2", DAMP, MEDIUM DENSE __7.0 ~7 NFS, DARK BROWN SAND WiTH ANGULAR TO SUBANCULAR · \GRACEL TO i", WET, MEDidM DENSE \ ~.~ CROUNDWATER LEVEL WHILE DRILLING (8,0 FT) NFS, BROWN SANDY GRAVEL, ANGULAR GRAVEL TO i.5". WET, DENSE TO VERY DENSE 12-5 26.0 LO6 TEST BORING COMPi. ETED 3/26/85 PVC STANDPIPE iNSTALLED NO WATER IN THE STANDPIPE ON 4/q/85 OR 4/10/85 KEY MA : MECHANICAL ANALYSIS LL : LIQUID LIMIT Pt = PLASTIC iNDEX PP : POCKET PENETROMETER (TSF) TV = TORVANE [TSFI ~ = GRAB SAMPLE [] = SPT SAMPLE [] : SHELBY TUBE-PUSHED [] = 2.5" i.D, SPOON SAMPLE 3~0# WEIGHT. 30" CALL T : SAMPLE TEMPERATURE (~F) PROBABLY A~FFCTED BY SAMPLING PROCEDURE DOWL ENGINEERS LOG OF BORING LOGGED BY CAROL KLEIN W-O. 051680 FIGURE 3 TEST BORING 3 LOCATiON=SEE TEST BORING LOCATION MAP ELEVATION= 276.0 :2, SiLTM SAND, mROZEN NFS/Fi, BROWN SANDY GRAVEL WiTH ABOUT 5% SiLT. ANGULAR TO SUBANGULAR GRAVEL YO 2", OCCASiONA~ COBBLES OR BOULDERS, DAMP. ~ERY DENSE DEPTH 0.5 T=33 t=42 ........................... 22.0 TEST BOR{NG COMPLETED 4/4/85 NO GROUNDWATER OBSERVED WHluE DRiuLiNG AdCER REFUSAu ON COBBLES OR BOULDER KEY MA = MECHANICAL ANALYSIS LL = LiOUiD LIMIT PI = PLASTIC INDEX pP = POCKET PENETROMETER (TSF) T¢ = TORVANE (TSF) [] = GRAB SAMPLE [] = SPT SAMPLE [] = SHELBY TUBE-PUSHED [] = 2,5" i.D. SPOON SAMPLE 340~ WEIGHT, 30" ;ALL T : SAMPLE rEMPEBAYURE !?F~ PROBABLY APFECTED DY SAMPLING °ROCEDURE DOWL ENGINEERS LOG OF BORING LOGGED BY CAROL KLEIN W.O. D5~683 FiCJRE 4 lO 15 5 ~2o 25 53 35 I T=42 F 2 T:41 L TEST BORING 4 =o~ ~ LOCA'FiON=SEE TEST BORING LOCATION MAP ~m ~ EL i ~,~1 . GRAY ELEVATION= 276.2 DEPTH F4. BROWN SILTY SAND, FROZEN, SOME SURFACE ORGANICS FI, BROWN SILTY GRAVEL WiTH SAND, ANGULAR/FLA~ GRAVEL TO 3". DAMP, CERY DENSE 1.5 CASiONAu COBBLES TO 5" NFS. BROWN SANDY GRAVEL, LESS THAN 5% SILT. ANOULAR GRAVEL TO 1.5". DAMP. DENSE 7.0 ........................... 21.5 TEST BORING COMPLETED 3/26/85 NO GROUNDWATER OBSERVED WHILE DRiLLiNG KEY MA = MECHANICAL ANALYSIS LL TM LIOUiD LIMIT PI = PLASTIC INDEX pP = POCKET PENETROMETER (TSF) TV = TORVANE (TSF) [] = CRAB SAMPLE [] = SPT SAMPLE [] = SHELBY TUBE-PUSHED [] = 2.5" i.O, SPOON SAMPLE 340# WEIOHT, 30" WALL f = SAMPLE TEMPERATURE (FF) PROBABLY AWFECTEB BY SAMPLING PROCEDURE DOWL ENGINEERS LOG OF BORING LOGGED BY CAROL KLEIN W.O. D51680 FIGURE 5 L o ::20 TEST BORING 5 LOCATiON=SEE TEST BORING LOCATiON MAP ELEVATION= 275,7 DEPTH 5--8 BROWN SILTY SAND WiTH ANGULAR GRAVEL TO i/2". -~TRACE OF SURFACE ORGANICS, ~ROZEN i.O NFS, BROWN SANDY GRAVEL WiTH SAND. GENERALLY LESS THAN 5% SiLT. ANGULAR TO SUBROUNDED GRAVEL TO 2.5", DAMP TO WET, DENSE TO VERY DENSE % ~7 GROUNDWATER LEVEL WHILE DRiLLiNG '2i .0 FT) ....... 33.8 TESf BORING COMPLETED 3/27/85 PYC STANDPIPE iNSTAuLEO NO WATER IN THE STANDPIPE ON 4/4/85 OR 4/10/85 KEY MA = MECHANICAL ANALYSIS LL = LIQUID LIMIT Pi TM PLASTIC INDEX pp = POCKET PENETROMETER (TSF) TV = TORVANE /TSF) [] = GRAB SAMPLE [] = SPT SAMPLE F~ = SHELBY TUBE-PUSHED [] = 2.5" ~ 9, SPOON SAMPLE 340# WEIGHT. 30" ~ALL T = SAMPLE TEMPERATURE IFF) PROBABLY AFFECTED BY SAMPLING PROCEDURE DOWL ENGINEERS LOG OF BORING LOGGED BY CAROL KLEIN W.O. D51680 FIGURE 6 f F io L 25 53 55 iS T:40 Iz~ T=50 T=$1 I4 TEST BORING 6 LOCATiON--SEE TEST BORING LOCATION MAP ELEVAfION= 275.6 DEPTH NFS/FI, BROWN SANDY GRAVEL WITH GENERALLY LESS THAN 5% SILT. ANGdLAR GRAVEL TO ~". )AMP. VERY DENSE GRAVELLY iMMEDiATELY BELOW GRASS COVER NFS, BROWN GRAVELLY SAND WiTH GENERALLY LESS THAN SZ SILT, ANGULAR TO SUBANCULAR GRAVEL TO DAMP, DENSE 18.3 ;7 __ 22.5 NFS, BROWN SANDY ANGULAR GRAVEL TO i-'~". DAMP, · ., VERY DENSE -- ......................... 3i .3 TEST BORING COMPLETED 3/28/85 NO GROUNDWATER OBSERVED WHILE DRiLLiNG KEY MA = MECHANICAL ANALYSIS LL = LiOdiD LIMIT Pi : PLASTIC iNDEX pp : POCKET PENETROMETER (TSF) T,/ = TORVANE (TSF) [] = GRAB SAMPLE [] = SPT SAMPLE ~ = SHELBY TdBE-PUSHED [] = 2.5" i.D. SPOON SAMPLE 340# WEIGHT, 30" =ALL T = SAMPLE TEMPERATURE (.'F) PROBABLY AFFECTED BY SAMPLING PROCEDURE DOWL ENGINEERS LOG OF BORING LOGGED BY CAROL KLEIN W.O. gSI680 FIGURE 7 35 ~ j2 CD-TX T:40 TEST BORING 7 LOCATiON=SEE TEST BORING LOCATION MAP ELEVATION= 275.8 DEPfH NFS/F1, BROWN SANDY GRAPEL WiTH ABOUT 5% SILT, ANGULAR TO SUBROUNDED GRAPEL TO 2.5". 3CCASiONAL COBBLES, DAMP. VERY DENSE ............................ 21.5 TEST BORING COMPLETED 4/i/85 NO GROUNOWATER OBSERVED WHILE DRiLLiNG KEY MA = MECHANICAL ANALYSIS LL : LiOUiD LIMIT Pi = PLASTIC INDEX pP : POCKET PENETROMETER (TSF) TV = TORYANE (TSF) [] = GRAB SAMPLE [] = SPT SAMPLE [] = SHELBY TUBE-PUSHED i~ = 2.5" i.D. SPOON SAMPLE 340# WEIGHT. $9" CALL z = SAMPLE TEMPERATURE (?F) PROBABLY AFFECTED BY SAMPLING PROCEDURE DOWL ENGINEERS LOG OF BORING ,.OGGED BY CAROL KLEIN W.O. DS1680 FIGURE 8 $ 1=42 =44 t4 :=45 TEST BORING 8 LOCATiON=SEE TEST BORING k. OCA~ lO MAP ELEVATION= 275.5 DEPTH GPI Fl, BROWN SANDY GRAVEL WiTH ABOUT 5% SILT, ANGULAR G.M.~GRAVEL TO 5". PROZEN "NFS/FI, BROWN SANDY GRAVEL WiTH ABOUT S% SiLTI ANOULAR GRAGEL TO 3". OCCASIONAL COBBLES TO 5'. DAMP. GERY DENSE OMi __7.5 NFS, BROWN SANDY GRAVEL WiTH GENERALLY tESS THAN 5Z SILT, ANGULAR TO SUBANGULAR GRAVEL TO DAMP, GERY DENSE iJ.3 Fl, DROWN SANDY GRAVEL WiTH ADOUT 5% SILT, ANGULAR TO SUBROUNDED GRAVEL TO 2.5", DAMP. GERY DENSE I6 TEST BORING COMPLETED 4/2/85 NO GROUNDWATER OBSERVED WHluE DRiLLiNG PUC STANDPIPE iNSTALLED NO WATER IN THE STANDPIPE ON 4/4/85 OR 4/10/85 KEY ~A = MECHAN~CA~ ANALYSIS ~L = LiQUiD Li~IT Pi = PLASTIC iNDEX pP = POCNET PENETROHETER (TSF) ~V = TORVANE (TSF) [] : GRAB SAMPLE ~ = SPT SAMPLE ~-~ = SHELBY TUBE-PUSHED ~ = 2.5" i.D. SPOON SAMPLE 540# WEIGHT, ~0" ~ALL T = SAMPLE TEHPERATURE (.'F) PROBABLY AFFECTED BY SAMPLING PROCEDdRE DOWL ENGINEERS LOG OF BORING LODGED BY CAROL KLEIN W.3. DSt 680 FIGURE 9 L~ ~O )S 2S 3O 35 14 T:4i !s T:55 i3 T=49 i3 r=5i ~,3 T=51 TEST BORING 9 LOCATiON:SEE TEST BORING LOCATION MAP ELEVATION: 27)..8 DEPTH NFS/Fi. BROWN SANDY GRAOEL WiTH ABOUT 5X SILT, ANGULAR TO SUBROUNDED ORAyEL TO 2.5", DRY TO DAMP. OERY DENSE MANY 3" COBBLES iN AUGER RETURNS .......................... 28,Q rEST BORING COMPLETED 3/29/85 NO GROUNDWATER OBSERVED WHILE DRiLLiNG PVC STANDPIPE iNSTALLED NO WATER IN THE STANDPIPE ON 4/~/85 OR q/10/85 KEY MA = MECHANICAL ANALYSIS LL : LiQUiD LIMIT Pi = PLASTIC INDEX pP = POCKET ~ENETROMETER !TSF) · ¢ = ~ORVANE (TSF) ~ = GRAB SAMPLE ]~ = SPr SAMPLE '~ = SHELBY TJBE-PUSHED '~ = 2,5" i:0. SPOON SAMPLE 340# WEIGHT, 30" FALL T = SAMPLE TEMPERATURE (-Fi PROBABLY AFFECTED BY SAMPLiNC PROCEDURE DOWL ENGINEERS LOG OF BORING LOGGED BY CAROL KLEIN W.O. D5~683 ciCUeE 10 i3 25 33 35 T=42 TEST BORING 10 LOCA'riON:SEE TEST BORING LOCATION MAP ELEVATION= 272,8 AS PAVEMENT F~, DROWN SILTY GRAVEL WiTH SAND, ANGULAR GRAVEL TO 2". vROZEN NFS/F1. DROWN SANDY GRAVEL WiTH ABOUT 5X SILT, ANGULAR GRAVEL TO 2.5". 3CCAS;ONAL CBBDLES ~3 4". DRY, VERY DENSE DEPTH 0.3 __8.3 NFS, DROWN SANDY GRAVEL WiTH CENERALLY LESS THAN 5% S;LT. ANGULAR TO SUBANGULAR GRAVEL TO 2", DAMP, VERY DENSE NFS/FI, BROWN SANDY GRAVEL WiTH ABOUT 5% SILT. .ANGULAR TO SUBROUNDED GRAVEL TO 2.5". DAMP, VERY DENSE °l · ~ 30.~ O0 TEST BORING COMPLETED 4/2/85 NO GROUNDWATER ODSERVED WHILE DRiLLiNG KEY MA = MECHANICAL ANALYSIS LL = LiOUiD Li~iT p; = PLASTIC iNDEX mR = POCKET PENETROMETER (TSF) T'¢ ~ TORVANE (~SF) ~ :- GRAB SAMPLE ~ = SPT SAMPLE ~ = SHELBY TUBE-PUSHED ~ = 2.5" i.D. Sm00N SAMPLE 340# WEIGHT. 33" ~ALL T = SAMPLE TEMPERATURE (fF) PROBABLY AVFECTED BY SAMPLING PROCEDURF DOWL ENGINEERS LOG OF BORING ~_OGGED BY CAROL KLEIN N.O. D51680 FIGURE 11 F 0 lO 15 ~2o 25 3O ~5 TEST BORING 11 LOCATiON=SEE TFST BORINC LOCATION MAP ELEVATION= 272,8 DEPTH NFS, BROWN SANDY GRAVEL WiTH GENERALLY LESS THAN 5% SILT, &NGULAR GRAVEL TO 2.S", DAMP, VERY DENSE FI, BROWN SANDY GRAVEL WiTH ABOUT 5% SILT, ENGdLAR GRAVEL TO 2" WiTH OCCASIONAL COBBLES TO 5". DAMP TO WET. DENSE TO VERY DENSE ~ GROUNDWATER LEVEL WHILE DRILLING (23.0 ~T) TEST BORING COMPLETED 3/28/85 PVC STANDPIPE iNSTALLED NO WATER IN THE STANDPIPE ON 4/4/85 OR 4/10/85 .$ KEY MA = MECHANICAL ANALYSIS LL = LiOUiD LiMiT Pi = PLASTIC iNDEX pP = POCKET PENETROMETER (TS?) TV = TORVANE (TSF) [] = GRAB SAMPLE ~ = SPT SAMPLE [] = SHELBY TUBE-PUSHED ~ = 2.5" i.D. SPOON SAMPLE 340# WEIGHT, 30" =ALL T = SAMPLE TEMPERATURE (/F) PROBABLY AFFECTED BY SAMPLING PROCEDURE DOWL ENGINEERS LOG OF BORING LOGGED BY CAROL KLEIN W.9. gs1680 FIGURE 12 F IL T~32 T=49 ~9 TEST BORING LOCATiON:SEE TEST BORING LOCATION MAP ELEVATi ON: 273.4 DEPTH ~iLL, Fi. BROWN SANOY GRAVEL WiTH SILT, ANGdLAR GRAVEL TO i.S". FROZEN 2.0 Fl. BROWN SILTY GRAVEL WITH SAND. ANGULAR GRAVEL TO 5", DRY, VERY DENSE THiN SILTY FiNE SAND LAYER __8.3 NFS/Fi, BROWN SANDY GRAWEL WiTH ABOUT 57 SILT. ANGJLAR TO SUBROUNDED GRAVEL TO 2-5". DAMP, WERY DENSE NFS BROWN SANDY GRAVEL W~TH GENERALLY LESS THAN 5% qiLT. ANGULAR TO SUBPOJNDED GRAVEL TO 2'.5". DAMP. WERY DENSE TEST BORING COMPLETED 4/5/85 NO GROUNDWATER OPSERWED WHILE DRiLLiNG KEY MA : MECHANICAL ANALYSIS ~L = L[OUiD uiM]T o[ = PLASTIC iNDEX PP = POCKET PENETROMETER (TSF) T¢ = TORVANE (TSF) [] = GRAB SAMPLE [] = SPT SAMPLE [] = SHELBY TUBE-PUSHED ~ = 2.5" i.D. SPOON SAMPLE 540# WEIGHT, $0" ~ALL T = SAMPLE TEMPERATURE (?F) PROBABLY AFfECtED BY SAMPLING PROCEDURE DOWL ENGINEERS LOG OF BORING ~.OCCED BY CAROL KLEIN W.O. 951680 FIGURE 13 f F %-. ~0 25 ~ L L i36 T=3O T=32 TEST BORING 16 lES. BORING LOCATION MAP LOCATiON:SEE ' T ELECATiON= 272.1 L DEPTH ASPHALT PAVEMENT 0.3 , JtIPILL, Fi, BROWN SILTY GRAVEL, ABOUT 5Z SILT. ~ENGU~AR GRACEL TO 1.5", PROZEN 2,0 PT - · ;'r ' ' ~ I FILL, F4, PEAT AND S,L, WITH ABOUT iSZ ORAVEL AND 40Z SAND, SOME CHUNCKS OF WOOD iN THE DRILL _~RETURNS, ~ROZEN 5.0 ~2. DARK BROWN SILTY SAND WiTH A TRACE O~ ORGANICS 3 T=39 5i DAMP, DENSE 7.S NFS, BROWN SANDY GRAVEL, 6ENERALLY LESS THAN 5% SILT, ANGULAR TO SUBROUNDED GRACEL TO 3'. DAMP, DENSE ........................... i6.3 TEST BORING COMPLETED 4/2/85 NO GROUNDWATER OBSERVED WHILE DRiLLiNG PVC STANDPIPE iNSTALLED NO WATER IN THE STANDPIPE ON 4/4/85 OR 4/10/85 KEY MA = MECHANICAL ANALYSIS LL = LiDdiD LiMiT Pi = PLAS=iC iNDEX Pp = POCKET PENETROMETER (TSF) ~V = TORVANE (TSF) '-~ = GRAB SAMPLE ~ = SP~ SAMPLE [] = SHELBY TUBE-PUSHED ~] = 2.5" i,D. SPOON SAMPLE 340# WEIGHT, 30" CALL T = SAMPLE {E~PEBArURE ('F) ~ROBABLY AFPEC~ED BY SAMPLING PROCEDURE 'DOWL ENGINEERS LOG OF BORING LOGGED BY CAROL KLEIN W.9. 951680 FIGURE 14 ~0 ~5 :20 25 30 i23 MA FIG.32i 4 T=36 ]5 T=4138 TEST BORING 17 LOCAtiON=SEE TEST BORING LOCAtiON MAP ELEVATION= 278.6 DEPTH BROWN SILTY RAND WiTH GRAVEL TO i", VROZEN NFS. BROWN SANDY GRAVEL WiTH GENERALLY LESS THAN 5Z SILT. ANOULAR GRAVEL TO ].~". DRY, VERY DENSE ,4.0 NFS. BROWN SANDY GRAVEL, LESS THAN 57 SILT. ANGULAR TO SUBANCULAR GRAVEL TO 2", DAMP, DENSE TO VERY DENSE 8.3 NFS, BROWN SANDY GRAVEL WiTH GENERALLY LESS THAN SM SILT, ANGULAR TO SUBANGULAR GRAVEL TO 2". OA'IP DENSE ........................... 16.3 TEST BORiNO COMPLETED 5/29/85 NO GROONDWA?ER OBSERVED WHILE DRiLLiNG =VC STANDPIPE INSTALLED NO WATER IN THE STANDPIPE ON 4/4/85 OR N/10/85 KEY HA : HECHANiCAL ANALYSIS LL = LiOJiO ~iM[? Pi = PLASTIC iNOEX PP = POCKET ~ENETROMETER (TSF) TV = TORVANE (TSF) [] : GRAB SAMPLE ~ = SPT SAMPLE ,~ = SHELBY TUBE-PUSHED [] = 2.5" ~ ~, SPOON SAMPLE 540# WEIGHT, 30" ~ALL T = SAMPLE TEMPERATORE (?F) PROBABLY AF:EC~FD BY SAMPLING ~ROCEDURE DOWL ENGINEERS LOG OF BORING ,.OGGEO BY CAROL KLEIN W.O. OSI680 ~iGURE 15 iD ~5 25 5O ,35 ~ ~ ~o TEST, BORING 18 ~ z o LOCATiON=SEE rEST BORING LOCATION MAP ~ ~ ~ DEPTH o v ~ ELEVATION= 280.1 33 ML'I~ :4, BROWN SANDY SILT. ABOUT 5Z DRACEL. SATUR. ,ED MA FIG, , . LL=36 IIL!~I'I--XAND VERY SDFT WHEN THAWED PI=7 ,I..-iF;':I Fi, BROWN SANDY GRAVEL WiTH ABOUT 5% SILT, ANGULAR I ~I TO SUBAN0dLAR GRAVEL TO 2", OCCASIONAL COBBLES, TEST BORING COMPLETED $/29/85 NO GROdNDWATER OBSERVED WHILE DRiLLiNG KEY MA = MECHANICAL ANALYSIS LL = LIOdiD LIMIT Pi = PLASTIC iNDEX pp = POCKET PENETROMETER (TS?) T¢ = TORVANE (TSF) [] = GRAB SAMPLE [] = SPT SAMPLE [] = SHELBY TUBE-PUSHED [] = 2.$" i.D, SPOON SAMPLE 340# WEIGHT, 30' :ALL T = SAMPLE TEMPERATdRE (/F) PROBABLY AFFECTED BY SAMPLiNC PROCEDdRE DOWL ENGINEERS LOG OF BORING LOGGED BY CAROL KLEIN w.o. D51680 FIGURE 16 iO i5 ~2o L 3O i19 SM KEY MA = MECHANICAL ANALYSIS LL = LiQdiD LIMIT Pi = PLASTIC iNDEX pp = POCKET PENETROMETER (TSF) TV ~ TORVANE (TSF) [] ~ GRAB SAMPLE [] = SPT SAMPLE [] = SHELBY TUBE-PUSHED [] = 2.$'" [.0. SPOON SAMPLE 340# WE[GHf. 30" ~ALL T = SAMPLE TEMPERATdRE (~F) PROBABLY AFFECTED B¥ SAMPLING PROCEDURE TEST BORING 19 LOCATION=SEE TEST BORING LOCATION MAP ELEVATION= 279.7 DEPTH m4, BROWN SILTY SAND WiTH ANGULAR GRAVEL TO 3/4". ~ROZEN Fl, BROWN SANDY GRAVEL WiTH ABOUT 5% SILT, ANGULAR GRAVEL TO 2". DRY TO DAMP, VERY DENSE OCCASIONAc COBBLES TO 5" 1.5 TEST BORING COMPLETED 3'29/85 NO GROUNDWATER OBSERVED WHILE DRILLING DOWL ENGINEERS LOG OF BORING LOGGED BY CAROL KLEIN W.O. D51680 FIGURE 17 i0 )5 25 3O 35 !4 T=35 T=42 TEST BORING 20 LOCATION:SEE TEST BORINC LOCATION MAP ELEVATION-: 279.2 DEPTH ~ILL, F4, BROWN SANDY SiLT WiTH GRAVEL TO 2.5". VERY DENSE, FROZEN 2-0 DARK BROWN PEAT ~,/iTH LARGE WOOD CHUNKS, DAMP. MEDIUM STIFF WHEN THAWED __4,0 F4. OLIVE SILTY SAND, TRACE OF ORGANICS DANP, DENSE 6.0 Fi, BROWN SANDY GRACEL WiTH ABOUT 5~ SILT, ANCULAR GRACEL TO 3". DAMP, CERY DENSE TEST BORiNC COMPLETED 3/28/85 NO GROUNDWATER OBSERVED WHILE DRILLING PVC STANDPIPE INSTALLED NO WATER IN THE STANDPIPE ON ~/5/85 OR ~/10/85 KEY MA = MECHANICAL ANAcYSiS cL = LiQUiD LIMIT Pl : PLASTIC INDEX PP = POCKET PENETROMETER ¢TSF] TV : TORVANE (TSF) [] : GRAB SAMPLE [] = SPT SAMPLE [] = SHELBY TUBE-PUSHED [] = 2.5" i.D. SPOON SAMPLE 340# WEIGHT, 30" ~ALL T : SAMPLE TEMPERATURE (3F) PROBABLY AFFECTED BT SAMPLING PROCEDURE DOWL ENGINEERS LOG OF BORING cOGGED BY CAROL KLEIN W.O. 951680 FIGURE 18 15 IlO ~ ~ ~ TEST BORING 21 u~ zo ~o LOCATiON=SEE TEST BORING LOCATION MAP ~- ~ ~ DEPTH o ~ ~ ELEVATION= 279.0 I ~' ! ~,ou,A, GRAVEL TO 2'. DRY. VERY DENSE ~.'~ ,,o,, I~' T=g5 ~ TEST BORINO COMPLETED 5/29/85 NO GROUNBWATER OBSERVED WHILE DRILLING KEY MA : MECHANICAL ANALYSIS ~L = LIOUiD LIMIT Pi = PLASTIC INDEX pp = DOCKET PENETROMETER (TSFI TV = TORVANE (TSF) ~ : CRAB SAMPLE [] = SPT SAMPLE [] = SHELBY TUBE-PUSHED ,~ = 2.5" i.9. SPOON SAMPLE 340# WEIGHT. 30" GALL T = SAMPLE TEMPERATURE (;F) PROBABLY AFFECTED BY SAMPLING PROCEBdRE DOWL ENGINEERS LOG OF BORING LOGGED BY CAROL KLEIN W,O. D51680 FiOURE 19 F 25 5O TEST BORING 22 LOCAtiON=SEE TEST BORING LOCATION MAP ELEYAr iON: 27~+, 8 OEPTH MA F1G.3E I I'~!~ ~2, BROWN SILTY SAND WITH ANGULAR GRAVEL TO ]". / ~*:~ ~'1. BROWN SANDY GRAVEL ~iTH ABOUT 5X SILT. ANGULAR T=46 ~,1 ......................... i36 TEST BORING COMPLETED 3/28/85 NO GROUNDWATER OBSERVED WHILE DRiLLiNG KEY MA = MECHANICAL ANALYSIS LL = LIQUID LIMIT Pi : PLASTIC INDEX PP = POCKET PENETROMETER mTSF) TV = TORVANE (TSF) [] : DRAB SAMPLE [] : SPT SAMPLE ~ = SHELBY TUBE-PUSHED [] = 2.5" ~,O. SPOON SAMPLE 340# WEIGHT, $0" mALL T = SAMPLE fEMPERATURE ('F) PROBABLY AFFEOTEB BY SAMPLING PROCEDURE DOWL ENGINEERS LOG OF BORING uOGGED BY CAROL KLEIN W.9. 95i 680 FiDURE 2O 15 ~2o 25 3O 35 8 iMA FIG.57 !LL=N7 T:44 TEST BORING 23 LOCATION:SEE TEST BORING LOCATION MAP ELEVATION: 275.N DEPTH F2, BROWN GRACELLY SAND WITH ABOUT 5% SILT .M.r~__...DAMP, MEDIUM DENSE __ _I 1.7 Tlli F4. OLIVE SILT WITH A TRACE OF ORGANICS AND SAND, ~ISUAL ICE CONTEN+ OF 10-15%, DAMP WHEN THAWED 4.0 ~J FI. OLIVE S,A, NDY GRACEL WITH ABOUT 5% SILT. ANGULAR '~L GRAVEL TO 2', DRY, VERY DENSE i ,,t ~I_ LAYER OF COBBLES 9.0 NFS, SANDY ANGULAR GRAVEL TO 2.5". LESS THAN 5X SILT, DAMP, CERY DENSE Il .3 TEST BORING COMPLETED 3/27/85 NO GROUNDWATER OBSERVED WHILE DRILLING PVC STANDPIPE iNSTALLED NO WATER IN THE STANDPIPE ON 4/5/85 OR 4/10/85 KEY MA = MECHANICAL ANALYSIS LL = LIQUID L. IMIT PI = PLASTIC INDEX PP : POCKET PENETROMETER ~TSF) TV : TDRVANE (TSF) [] : GRAB SAMPLE [] : SPT SAMPLE [] = SHELBY TUDE-PUSHED [] = 2.5" i.D. SPOON SAMPLE 340# WEIGHT, 30" ~ALL f = SAMPLE TEMPERATURE (?F) PROBABLY AFFECTED BY SAMPLING PROCEDURE DOWL ENGINEERS LOG OF BORING LOGGED BY CAROL KLEIN W.O. 951680 FiGORE 21 'r=4O T=36 TEST BORING 24 LOCATiON=SEE TEST BORING LOCATION MAP ELEVATION= 271.3 DEPTH I F4, OL]¢E BROWN SANDY SiLT WITH SOME ORGANICS. ~SOME GRAVEL, FROZEN NFS/FI , BRaY ~RA~---'~EL W'~]T~ ABO-~T~ SiLT- - .'~¢S/Fi, OLIVE SANDY GRAVEL WiTH ABOUT 5% SILT, SUBROUNDED TO SUBANCULAR 6RAVEL TO DAMP, DENSE 54 TEST BORING COMPLETED 4/5/85 NO GROUNDWATER OBSERVED WHILE DRiLLiNG O.S B.O .5 KEY MA = MECHANICAL ANALYSIS LL = LiQUiD LIMIT ¢; = PLASTIC iNDEX pp : POCKET PENETROMETER (TSF) TV : TORVANE [] = GRAB SAMPLE [] = SPT SAMPLE ~ = SHELBY TUBE-PUSHED [] = 2.S" i.D, SPOON SAMPLE 340# WEIGHT, 50" ~ALL T = SAMPLE TEMPERATURE (~F) ~ROBABLY AFFECTED BY SAMPLING PROCEDURE DOWL ENGINEERS LOG OF BORING LQGGEO BY CAROL KLEIN W.O. OS1680 F[CdRE 22 0 I0 15 2S 5O 35 T=41 L ~ TEST BORING 25 ~ LOCATiON:SEE TEST BORING LOCATION MAP 0 u_ ELEVATION: 282.3 iii NFS/F1, BROWN SANDY GRAVEL WiTH ABOUT 5% SILT, · ANGULAR TO SUBANGULAR GRACEL TO 3'." DAMP, VERY DENSE LARGE COBBLE TEST BORING COMPLETED 4/i/8S NO GROdNDWATER 08SERVED WHILE DRILLING PVC STANDPIPE iNSTALLED NO WATER IN STANDPIPE ON 4/5/85 OR 4/10/$5 DEPTH KEY MA : MECHANICAL ANALYSIS LL : LiOUiD LIM[T Pt = PLASTIC INDEX pp : POCKET PENBTRDMETER {TSF) TV : TORVANE (TSF) [] = BRAD SAMPLE [] : SPT SAMPLE [] = SHELBY TUBE-PUSHED ~ = 2.5" i.D. SPOON S'AMPLE 540# WEIGHT. 30" ~ALL T = SAMPLE TEMPERATURE (,'F) PROBABLY AFFECTED BY SAMPLING PROCEDURE DOWL ENGINEERS LOG OF BORING LOGGED BY CAROL KLEIN W.O. DS~680 FIGURE 23 -~~ TEST BORING 26 ='o LOCATiON=SEE TEST BORING LOCATION MAP ~ u_ ELEVATION= 285.q DEPTH >)~S~~I~FI, OLIVE SILTY GRAVEl. WiTH SAND. MANY COBBLES, THE NUMBER AND SiZE OF THE COBBLES iNCREASiNG WiTH DEPTH UNTIL iT iS ALMOST ALL COBBLES AND/OR BOULDERS AT AND BELOW 6 FEET . BOULDERS TO 15' ON THE SURFACE NEAR TEST BORING TEST BORING COMPLETED 4/3/85 NO GROUNDWATER OBSERCED WHILE DRiLLiNG KEY MA = MECHANICAL ANALYSIS LL : LIQUID LIMIT Pi = PLASTIC INOEX pp = POCKET PENETROMETER (TSF) T~ = TORVAflE (TSF) [] ~ GRAB SAMPLE [] : SPT SAMPLE [] = SHELBY TUBE-PUSHED [] = 2.5" i.D. SPOON SAMPLE 340# WEIGHT, 30" ~ALL T = SAMPLE TEMPERATURE (~F~ PROBABLY AKFECTED BY SAMPLiNC PROCEDURE DOWL ENGINEERS LOG OF BORING LOGCED BY CAROL KLEIN W,O. OSi 680 FIGURE 24 T=32 T=33 T=3S o TEST BORING 27 ~ ~ LOCATiON=SEE TEST BORING LOCATION MAP ~ u_ ELEVATION= 278.3 DEPTH 29~ FILL, FI, BROWN SILTY DRACEL WiTH SAND, ANGULAR GRAVEL TO 2". FROZEN 4.5 ¢ir Fi, BROWN SANDY GRAVEL WiTH ABOUT iOZ S~LT, GP ANCULAR TO SUBROUNDED GRAVEL TS ;,5" DAMP. VERY DENSE NFS. BROWN SANDY GRAVEL WiTH GENERALLY LESS THAN 5Z SILT, ANGULAR TO SUBROUNDEP CRA'CE;' TO DAMP. VERY DENSE 47 TEST BORING CgHPLETED a/4/85 NO GROUNDWATER OBSERVED WHILE DPiLLiNG ~VC STANDPIPE iNSTALLEO NO WATER IN THE STANDPIPE ON 4/$/85 OR 4/10/85 KEY MA = MECHANICAL ANALYSIS LL : LiOUIO LIMIT Pi = PLASTIC iNDEX PP = POCKET PENETROHETER (TSF) T¢ = TORVANE (TSFI [] = GRAB SAMPLE [] = SPT SAMPLE [] = SHELBY TUBE-PUSHED [] = 2,5" [,O. SPOON SAMPLF 3aO# WEIGHT, 30" FALL T = SAMPLE TEMPERATURE (.'F~ PROBABLY AFFECTED BY SAMPLiNO ~ROCEDURE DOWL ENGINEERS LOG OF BORING LOGGED BY CAROL KLEIN W.O. gsi 680 FiOJRE 25 iO T=32 4 T=35 ~8 KEY MA = MECHANICAL ANALYSIS LL = LIOUiD LIMIT Pi - PLASTIC iNDEX PP = POCKET PENETROMETER (TSF) TV = TORVANE (TSF) [] = GRAB SAMPLE [] = SPT SAMPLE [] = SHELBY TUBE-PUSHED [] = 2.5" i.D. SPOON SAMPLE 340# WEIGHT. 30" ~ALL T : SAMPLE TEMPERATURE (:F) PROBABLY AFFECTED BY SAMPLING PROCEDURE TEST BORING 28 LOCATiON=SEE TEST BORING LOCATION MAP ELEV ~,T l ON-- 276.0 DEPTH Fl BROWN SILTY CRAVEL WiTH SAND, ABOUT i5% SILT. SUBANOULAR TO ANGULAR GRAVEL TD 1.4", cROZEN NFS/Fl. BROWN SANDY GRAVEL WiTH ABOdT 5% SILT, ANGULAR TO SUBROUNDED GRAVEL TO i.5". OCCASIONAL 3" COBBLE, DAMP, VERY DENSE · TEST BORING COMPLETED 4/I/85 NO GROdNDWATER OBSERVED WHILE DRILLING .S DOWL . ENO I NEERS LOG OF BORING LOGGED BY CAROL KLEIN W-O. 051680 FIGURE 26 T=3i T=42 TEST BORING 29 zo LOCATiON=SEE TEST BORING LOCATION MAP ~ ~_ ELEVATION= 262.0 DEPTH FILL, F2, BROWN SiLTY SAND WITH GRAVEL TO I", ~FROZEN ......... . 0 FILL. FI, BROWN SILTY SRAVEL WITH SAND, ANGULAR TO SUBROUNDEO GRAVEL TO 2'", OCCAS1DNAL 3" COBBLES,  WOOD CHIPS, ROOT ~iBERS AND STEMS, ~ROZEN ~ Fi, BROWN SANDY GRAVEL WiTH ABOUT, i0% SILT, r~'] ANGULAR T0 SUBANGULAR GRAVE[. TO J'. DAMP, VERY DENSE 29 TEST BORING COMPLETEO 4/5/85 NO GROUNDWATER OBSERVED WHILE O~ILLiNG PVC STANOP~PE iNSTAcLED NO WATER IN THE STANOPIPE ON 4/5/85 OR ~/10/85 KEY MA = MECHANICAL ANALYSIS LL = LiOUID LIM]T Pi : PLASTIC iNDEX pp = POCKET PENETROMETER rTSF) TV = TORVANE (TSF) [] = CRAB SAMPLE [] = SPT SAMPLE [] = SHELBY TUBE-PUSHED ~ = 2.5" i.O- SPOON SAMPLE J40~ WEIGHT, ~0'1 ~ALL T = SAMPLE TEMPERATURE (?F) PROBABLY AFFECTED BY SAMPLING PROCEDURE DOWL ENGINEERS LOG OF BORING LOGGED BY CAROL KLEIN W.0. D5}680 FIGURE 27 T=31 T=3S T=41 TEST BORING 30 ~OC&TiON=SEE TEST BORING LOCATION MAP ELEVATION= 261.1 DE~TH FiLL. F2, DARK BROWN S]LTM SANG WiTH ANOd~AR GRAVEL TO l", FROZEN 1.O FILL, F4, BROWN SiLTY PEAT WITH GRAVEL TO 2,5", FROZEN NFS/F1, BROWN SANDY GRAVEL WiTH ABOUT 5Z Si~~, ANGULAR TO SUBROUNDED GRAVEL TO ~1'. DAMP, VERY ~2, BROW-~---. ORAVEL,--~TsANG W~T~A~OUT ~ T-~ io~ S~T'--%B'° __ANGdLAR GRAVEL TO i", DAMP. VERY DENSE ~4 TEST BORING COMPLETED 4/3/85 NO GROdNDWATER OBSERVED WHILE DRILLING KEY MA = HECHAN~CAu ANALYSIS ~L : LIOUiD LiMIT ~I = PLASTIC iNDEX PP = POCKET PENETROMETER rTSF) TV = TORVANE (TSF) [] = GRAB SAMPLE [] = SmT SAMPLE I~] = SHELBY TUBE-PUSHEO [] = 2.5" i.D- SPOON SAMPLE 340# WEIGHT, 30" ~ALL T : SAHPLE TEMPERATdRE (?F~ PROBABLY AFFECTED BY SAMPLING PROCEDURE DOWL ENGINEERS LOG OF BORING LOGGED BY CAROL KLEIN W.O. OSi 680 FiGdRE 28 T=32 MA FIG.38 T=42 TEST BORING 31 LOCATiON--SEE TEST 80RING LOCATION MAP ELEVATION= 266.7 DEPTH  ~PEAT, SOFT. WET 0 I~U~--~x~\'F4, OLIVE SiLT WITH ORGANICS, NONPLASTiC. FROZEN [~l~ FI, OLiCE SILTY GRAVEL WiTH 10 TO 30% SILT, ~]~ SUBROUNDED GRA~EL T0 2,5". SOME SAND, 15~ DAHP~ DENSE . 59 ~ ...... ~.O NFS/Fi, BROWN SANDY GRAV'EL ~iTH GENERALLY  ABOUT 5% SILT, DAMP, VERY DENSE ~ ..... . ..................... ti.~ 128 ~,, TEST BORiN9 COMPLETED N0 GROUNDWATER 08SERVED WHILE DRIULiNG ~VC STANDPIPE iNSTALLED NO WATER IN THE STANDPIPE ON 4/5/85 OR 4/10/85 KEY MA = MECHANICAL ANALYSIS LL : LIOUiO LIMIT Pi = PLASTIC iNDEX PP = POCKET PENETROMETER ~TSF) TV : TORVANE fTSF) [] = GRAB SAHPLE [] = SPT SAMPLE [] = SHELBY TUBE-PUSHED [] = 2.5" i-O. SPOON SAMPLE 340# WEIGHT, 30" WALL T : SAMPLE TEMPERATURE (YF) PROBABLY AFFECTED BY SAMPLING PROCEDURE DOWL ENGINEERS LOG OF BORING ~OG~ED BY CAROL KLEIN W.0. 051680 FiGJRE 29 T=33 TEST BORING 32 LOCATION=SEE TEST BOR1NG LOCATION MAP ELEVATION= 276.2 DEPTH ~2, BROWN SiLTY SAND WITH SO~E GRAVEL. :ROZEN 1.3 NFS. BROWN GRAVELLY SAND.'ANGULAR TO SUBROUNDED GRAVEL TO 2". GENERALLY LESS THAN 5% SILT. DAMP, DENSE NFS BROWN SANDY GRAVEL WiTH GENERAL~.Y ~.ESS THAN 57 S JeT, ANGULAR TO SUBROUNDED GRAVEL TO 2", OCCASIONAL COBBLES $"~. DAMP, DENSE Fl. BROWN SANDY GRAVEL ~iTH ABOUT i0% SiLT. ANGULAR GRAVEL TO 2" GRADING TO 3-4" COBBLES DAMP. VERY DENSE ........................... i7.0 TEST BORING COMPLETED 4/4/85 NO GROUNDWATER OBSER,¢ED WH~LE DRiLLiN¢ AUGER REFUSAL ON A BOULDER? · MOVED iO ~T NORTH AND REDR1LLED AS TEST BORING 32A KEY MA = MECHANICAL ANALYSIS ~L : LIOUiD LIMIT Pi : PLASTIC iNDEX pP : POCKET PENETROMETER (TSF) TV : TORVANE (TS~) [] = GRAB SAMPLE [] = SPT SAMPLE ~ = SHELBY TUBE-~UBHED [] = 2.5" i.D. SPOON SAMPLE 340# WEIOHT. 30" CALL T = SAMPLE TEMPERATdRE (iF) PROBABLY A~FECTED BY SAMPLING oROCEDdRE DOWL ENGINEERS LOG OF BORING ~.OGCED PY CAROL KLE;N W.O. DS16PO FIOJRE 30 TEST BORING 32A LOCATiON=SEE TEST BORING LOCATION MAp ELE'¢ATION= 276.q :2. BROWN SILTY SAND WiTH SOME GRAVEL, :ROZEN NFS, BROWN SANDY GRAVEL WITH GENERALLY LESS THAN S% SILT, ANGULAR TO SUBBCUNDED GRAVEL TO 3" GRADING TO COBBLES TO 4"+ WiTH DEPTH, DAMP. VERY DENSE DEPTH i.O T:44 FI, BROWN SANDY GRAVEL WiTH ABOUT i07 SILT. ANGULAR TO SdBROUNDED ORACEL TO 2.5". DAMP. MED;UM DFNSE TO P~NSE 4.0 __ 8.5 F2. OLIVE S~LTY SAND WiTH ANGULAR GRAVEL TO i" SATJRATED, DENSE, (9~D LEACH FIEND AREA?! SEWER-LiKE ODER EMANATING FROM THE BORE HOLE GROUNDWATER LEVEL WHILE DRiLN:NG (20.0 ~T) -- 23.0 Fl, OLIVE SANDv TRAVEL WiTH ABOdT i0% SiLT ANGULAR GRAVEL TO ~.4- OAMP, CERY DENSE T=47 39 27.5 OLIVE BROWN SANDY GRACEL WiTH ABOUT iS~ SILT. SdBROdNDED TO SUBANGdLAR GRACEL TO 2' WET. DENSE TEST BORING COMPLETED 4/4/85 KEY MA : MECHANICAL ANALYSIS ~L = LiOdiD LIMIT Pi = PLASTIC iNDEX PP = POCKET PENETROMETER {TS:) T¢ = TORVANE (TSF~ [] = GRAB SAMPLE [] = SPT SAMPLE [] = SHELBY TUBE-PUSHED [] = 2.5" i.D. SPOON SAMPLE 340# WEIGHT. 30" ~ALL T = SAMPLE TEMPERATURE (:F) PROBABLY A~:ECTED BY SAMPLING PROCEDURE DOWL ENGINEERS LOG OF BORING uOGGFD BY CAROL KLEIN W.O. gSlGBO FIGURE 31 o _o ~o ~o o ~o $ ~o 0 _0 0 o _o ~o ~ o o 8 o o ~o ~ _0 0 o _o ~o o o g $ o _o ~o o ~o ~ ~o _0 0 I I I I 1Sd) (ISc~) SS3~/S ~O±BIA3O Z Z W 0~ W 0_ I I I I I I ( IS~J SSBNIS NO_L~J I Aq~ p- Z W W 0_ TIE L_ ~' -- 125 PCF ko =0.4 kp =4.2 ~D kp :5000 ko ~ / ko NOT t__O SCALE  ISTEESS DISTRIBUTION i HIGH SCHOOLI IAGAINST SHEET PILE CHUGIAK ENGINEERS[ RETAINING STRUCTURE W.O. D51680 [ FIG. 49 CHUGIAK HIGH SCHOOL~ ( EXISTING BUILDING ) ~ '~' · SHADED AREA ON ~ O O O O O O O O O O O O 0 ~ ~- ~ ~ 0 ~ ~ ~ ~ 0 RESISTIVITY LOWS ~ ~recision of a laboratory testing procedure. If the log includes soils samples, verify the field examination, Depth Interval - usually shown to 0.1 foot, within that zone no ~ignificant change tn soil type was observed through drill action, direct observation or sampling. Frost Classification - NFS. Fl, F2. F3, F4, see "Soil Classification Texture of Snil - An engineering classification of the soils by particle size and proportion, see "Soil Classification Chart", note the proportions ,ire approximate and modifications to the soil group due to stratification, inclusions and chauges In properties are included. daI'~lp, lno stur¢ forms portion ut color, less than pins c 1 m t, saturated, free water may be squeezed out, ifa free draining soil; dilatcnt at natural moisture content, if' a non-plastic silt or fine sand. (The moisture content is further definedby reference to PI, LW. NP. M% or dilatency.) Density - refers to more-or-less non-cohesive soils, such as sand gravel mixtures with or without a fine fraction, derived from drilling action and/or sample data; usually described as: very loose, loose, medium Stiffness - refers to more-or-less cohesive soils and fine grained silts of the clay-silt groups. Derived from drill action and/or sample data. Very soft, soft, stiff, very stiff and hard are commonly used terms. Particle size - The largest particle recovered by the split spoon is 1-3/8", Shelby tube Y', auger flights (minute-man) 2", Auger flights (B-S0 hollow stem) 6"-8". Larger particles are described indirectly by action of tile drilling and are referred to as cobbles. 3" to g", or boulders 8"+. Therefore when reviewing the gradation sheets, if any, the description on the hole log must be considered for an:indication of larger particles. Unified Soil Classification - This is a two letter code, See Unified Classification sheet for further definition. In some cases AASHO and/or FAA soil classifications may be shown aa well as the unified. Atterberg Limits - useful for tine grained and other plastic ~oils. Pi; natural moisture content believed to be less than plastic limit PI+; natuxal moisture content believed to be between plastic and liquid ITmit s L.~; natural moisture content believed to be greater than liquid limit N.._~P; non-plastic, useful as a modifying description of some silty mat~ri~h, Dilatency - is the ability of water to migrate to the surface of a saturated or nearly saturated soil sample when vibrated or jolted - used as an aid to determine if a fine grained soil is a slightly or non-pi&stat silt or a volcanic ash. Test Hole Log - Description Guide Rock flour - finely ground soft that is not plastic but otherwise appears similar to a clayey silt, Organic Content - usually described as Peat. PT. sometimes includes ' discrete particles such as wood, coal, etc. as a modifier to an inorganic soil. Quantity described as; trace, or an estimate of volume, or, in case of all organic. - as Peat. This may include tundra, muskeg and bog material. Muck -- a modifier used to describe very soft, semi-organic deposns usually occuring below a pe~tt depusit. Amorphus peat - organic particles nearly or fully disintegrated. Fibrous Peat -- organic particles more-or-less intact. Bottom of Testhole - includes last sample intervah Frost Line - seasonal frost depth as described by drilling action and/or samples at the time of drilling. Frozen Ground - other than frost line, described by samples, usually includes description of ice content, often will include modified Unified Classification for frozen soils - this is a special case related to permafrost studies. Free Water Level - The free water level noted during drilling. This is not necessarily the static water table at the time of drilling or at other seasons, Static water table determination in other than very permeable soils requires observation wells or piezometer installations, used only m special cases, Blow/6" - The number of blows of a 140 weight free falling 30" to advance a 2" split spoon 6"; the number of blows for a 12" advance is. by d~finition, the standard penetration. ,d% - natural moisture content of the soil sample, usually not p-'~'rformed on clean sands or gravels below the water table. Type of Sample - S__P, refers to .2'! split.spoon driven into the soil by 140 pound weight, a disturbed sample, S, thin wall tube, "Shelby" used to obtain undisturbed samples of fine grained soil, G, "grab" disturbed sample from auger flights or wall of trench, ~ cut sample, undisturbed sample from wall of trench. Dry Strength - a useful indicator of a soil's clayey fraction, N=None. L=Low, M=Medium, H=High Group - The samples are placed into apparently similar groups based on color and texture and are arbitrarily assigned a group letter. Further disturbed tests including Atterberg Limits, grain size, moisture~lensity relationship, etc. may be performed on the group and are assumed to reflect the general distrubed characteristics of the soils assigned to the group. Thi~ is an important phase of the soil analysis and is used to standardize the various qualitative determinations and to reduce the number of quantitative tests necessary to describe the soil maas. GRAVEL TEXTURAL S01L CLASSIFICATION CHART CLAY CLAYE .~LAYE~ OR SILT' GRAVEL GRAVELLY SAND GRAVEL 0 I0 20 30 40 50 60 70 80 90 GRAVEL (+ :~4 SCREEN) % BY WEIGHT 100 FROST CLASSIFICATION SYSTEM NONFROST SUSCEPTIBLE SOILS ARE INORGANIC SOILS CONTAINING LES5 THAN 3% FINER THAN 0,02 mm. GROUP5 OF FROST-SUSCEPTIBLE SOILS: F1 GRAVELLY SOILS CONTAINING BETWEEN 3 AND 20% FINER THAN 0.02 mm. F2 SANDY SOILS CONTAINING BETWEEN 3 AND 15% FINER THAN 0.02 mm, F3 a. GRAVELLY SOILS CONTAINING MORE THAN 20% FINER THAN 0.02 mm. AND SANDY SOILS (EXCEPT FINE SIL:TY, SANDS) CONTAINING MORE THAN 15% FINER THAN 0.02 mm. b. CLAYS WITH PLASTICITY INDEXES OF MORE THAN 12. EXCEPT VARVED CLAYS. F4 a. ALL SILTS INCLUDING SANDY SILTS. b. FINE SILTY SANDS CONTAINING MORE THAN 15% FINER THAN 0.02 mm. c, LEAN CLAYS WITH PLASTICITY INDEXES OF LESS THAN 12, d. VARVED CLAYS. PREVIOUS IESI BORINGS 1984 F S MA 0 NOTE; TEST BORING 45 LOCATION=NO SURVEY. APPROX. STATION 2220+86 ELEVATiON~2§i.0 (APPROX.) SEE NOTE BELOW Fi, BROWN SANDY GRAVEL FILL. CONCRETE FRAGMENTS. DAMP. DEPTH COBBLES TO 8"+. F1 + F4. BROWN SILTY SANDY GRAVEL FILL INTERMIXED WITH PEAT AND WOOD. MATERIAL USED TO FiLL PRE- EXISTING TOPOGRAPHIC DEPRESSION. SOFT, DAMP. 12.5 NFS. BROWN SANDY ~RAVEL TO 2''+. OCCASIONAL COBBLES TO 6"+. DAMP, CERY DENSE, COBBLE LAYER __ ~6,0 FI. BROWN SILTY SANDY GRAVEL TO 2"*. SUBROUNDED, DAMP. VERY DENSE. TEST BORING COMPLETED 8/i/84 NO GROUNDWATER OBSERVED WHILE DRILLING SiTE HAS BEEN REGRADED AND RESURFACED FOR NEW PLAYING FIELD AND TRACK AT CHUGiAK HIGH SCHOOL. ELEVATION HAS CHANGED SINCE SURVEY. STATIONING AND OFFSETS ARE BASED ON DESIGN DATA AS OF 11/2/84 18.0 KEY MA ~ MECHANICAL ANALYSIS LL = LIOUID LIMIT PI = PLASTIC iNDEX PP = POCKET PENETROMETER (TSF) TV = TORVANE (TSF~ [] = GRAB SAMPLE [] ~ SPT SAMPLE [] = SHELBY TUBE-PUSHED [] = 2.5" I.D. SPOON SAMPLE 3~O# WEIGHT. 30" FALL T = SAMPLE TEMPERATURE IFF) PROBABLY AFFECTED BY SAMPLING PROCEDURE DOWL ENGINEERS LOG OF BORING LOGGED BY TB W,O, D50884 FIGURE B45 MA 47 TEST BORING 46 LOCATiON=NO SURVEY. APPROX. STAT]ON 2222+61 ELEVATION-- 261.0 (APPP. OX.} SEE NOTE BELOW DEPTH F2/F4, BROWN SILTY GRAVELLY SAND FILL WITH 4"+ COBBLES. DAMP, LOOSE, F4, BROWN PEAT AND WOOD FILL. CET. SOFT. MATERIAL USED TO FiLL PRE-EXiSTING DEPRESSION. __4.5 FI . BROWN SILTv SANDY GRAVEL TO 1-]/21'+. SUBROUNDED, DAMP. DENSE. __ 13.0 COLOR CHANGES TO GRAY 21 .5 TEST BORING COMPLETED 7/31/84 NO GROUNDWATER OBSERVED WHILE DRILL]NO SiTE HAS BEEN REGRADED AND RESURFACED FOR NEW PLAYING FIELD AND TRACK AT CHUG1AK HIGH SCHOOL. ELEVATION HAS CHANGED SINCE SURVEY. NOTE: STATIONING AND OFFSETS ARE BASED ON DESIGN DATA AS OF 11/2/8~ KEY MA = MECHANICAL ANALYSIS LL = LIOUID LIMIT PI : PLASTIC INDEX PP = POCKET PENETROMETER (TSF) TV = TORVANE (TSF) [] = CRAB SAMPLE [] = SPT SAMPLE [] = SHELBY TdBE-PUSHED [] = 2.5" i.D. SPOON SAMPLE 340# WEIGHT, 30" ~ALL T = SAMPLE TEMPERATdRE (.'F) PROBABLY AFFECTED BY SAMPLING PROCEDURE DOWL ENG! NEERS LOG OF BORING LOGGED BY TB W.O. D50884 FIGURE ¢46 NOTES VERTICAL CONTROL LEGEND ::{EINFORCED CONCRETE SEPTIC TANK (~ SANITARY CLEANOUT NTS (~ DOSING CHAMBER PLAN VIEW (~ DOSING CHA~MBER )DRAIN BED SECTION DRAIN BED PLAN VIEW NTS DT1002611 z %% % DT1092612