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HomeMy WebLinkAboutGeotechnical InvestigationU" REPORT PRELIMINARY GEOTECHNICAL INVESTIGATION CHALET MARSEILLES SUBDIVISION MERIDIAN, IDAHO SEPTEMBER 4, 2007 FOR RC MERIDIAN PARTNERS, LLC Report Preliminary Geotechnical Investigation Chalet Marseilles Subdivision Meridian Idaho File No. 16566-001-00 Prepared for: September 4, 2007 RC Meridian Partners, LLC c/o J-U-B Engineers, Inc. 250 South Beechwood, Suite 201 Boise, Idaho 83709 _ Attention: Jim Coslett, PE Prepared by: GeoEngineers, Inc. 1525 South David Lane _ Boise, Idaho 83705 (208) 433-8098 GeoEngineers, Inc. Brent W. Hardy, CPSS Soil Scientist qIq 1296 Steven B. Richey, PE F OF P �� Principal B. R�G� B WH:SBR:mlh Boise:\16\16566001\00\Finals\1656600100R GT.doc Disclaimer: Any electronic form, facsimile or hard copy of the original document (email, text, table, and/or figure), if provided, and any attachments are only a copy of the original document. The original document is stored by GeoEngineers, Inc. and will serve as the official document of record. Copyright© 2007 by GeoEngineers, Inc. All rights reserved. File No. 16566-001-00 TABLE OF CONTENTS INTRODUCTION...................................................................................................... SCOPEOF SERVICES............................................................................................ SITECONDITIONS.................................................................................................. SURFACE CONDITIONS.................................................... ........................... SUBSURFACE CONDITIONS........................................................................ CONCLUSIONS AND RECOMMENDATIONS......................................................... GENERAL... .................... SITE GRADING ............................... Suitability of On -Site Soil........................................................................ SitePreparation..................................................................................... StructuralFill Criteria.............................................................................. Structural Fill Placement ......................... DESIGN/CONSTRUCTION CONCERNS........................................................ TEMPORARY EXCAVATIONS........................................................... STORMWATER INFILTRATION CONSIDERATIONS ..................................... Depthto Groundwater............................................................................. InfiltrationRate........................................................................................ _ PAVEMENT RECOMMENDATIONS............................................................... DRAINAGE CONSIDERATIONS ..................................................................... CORROSION POTENTIAL .................................................... LIMITATIONS.............................................................................................................. List of Tables Table 1. Allowable Infiltration Rates .............................. Table 2. Recommended Pavement Section for Residential Street ............................ Table 3. Corrosivity Testing Results. .............. ....................................................... List of Figures Figure 1. Vicinity Map Figure 2. Site Plan APPENDICES APPENDIX A — FIELD EXPLORATION AND LABORATORY TESTING Appendix A Figures Figure A-1. Key to Exploration Logs Figures A-2 — A-9, Logs of Test Pits Figure A-10. Atterberg Limits Test Result Figure A-11, R-Value Test Result APPENDIX B — REPORT LIMITATIONS AND GUIDELINES FOR USE File No. 16566-001-00 September 4, 2007 Page i ............2 ............2 ............3 .... 3 ............3 ........... , 3 ...........4 ..........4 ...........5 ........... 5 ...........6 ...........6 ...........6 ..........7 ..........8 ..........8 ..........9 .............6 ............. 8 .............8 GEoENGINEER� �r REPORT PRELIMINARY GEOTECHNICAL INVESTIGATION CHALET MARSEILLES SUBDIVISION MERIDIAN, IDAHO FOR RC MERIDIAN PARTNERS, LLC INTRODUCTION I L This report presents the results of our preliminary geotechnical investigation for the Chalet Marseilles Subdivision located on the corner of North Locust Grove Road and East Ustick Road in Meridian, Idaho. The property consists of two parcels that comprise approximately 21.81 acres in area. The property is surrounded by private property to the north and west, and to the south and east by public roadways. The approximate project area is shown in the VicinityMap, p, Figure 1. We understand the proposed project will consist of one- and two-story townhomes that are wood -frame, �. lightly loaded buildings (approximately 800 pounds per lineal foot) and concrete slab -on -grade floors. The project will also include a one-story clubhouse, asphalt concrete parking and access roadway areas, and possibly stormwater infiltration basins and subsurface infiltration galleries. Power, gas, water and sewer will be provided by public utilities. We also understand that roadway grades will require cuts of approximately 6 inches to fills of approximately 1 foot. The proposed site layout is shown on the Site Plan, Figure 2. 6w SCOPE OF SERVICES LOur services were completed in general accordance with our proposal dated May 15, 2007, which was signed on May 23, 2007 by RC Meridian Partners, LLC. Notice -to -proceed was authorized on August 3, 2007 by J-U-B Engineers, Inc. The purpose of our study was to provide preliminary geotechnical L information for use in project planning. Specifically, we completed the following scope of services: 1. Reviewed available published soil and geologic information for the project area. Lr 2. Coordinated Idaho State "Dial -Before -You Dig" contractor prior to excavating test pits at the site. 3. Excavated, logged, and sampled a total of eight test pits. Piezometers were installed in each test pit. 4. Performed laboratory testing that included particle size analysis, sieve, Atterberg limits (plasticity),percent passing US No. 200 corrosivity (pH, sulfates, resistivity) and resistance value � (R-value) tests. 5. Provided earthwork recommendations including subgrade preparation, structural fill placement, structural fill criteria, and evaluation of on -site soils for use as structural fill. 6. Developed estimated allowable infiltration rates for design of the proposed stormwater facilities based on soil classification and published literature only. 7. Provided pavement recommendations for residential streets. File No. 16566-001-00 September 4, 2007 Page 1 GEOENGINEER .. SITE CONDITIONS SURFACE CONDITIONS The property, comprised of two parcels, is approximately 21.81 acres in size and was recently farmed. The property slopes down to the west-northwest. There is an approximate maximum elevation difference of 4 feet between the east side of the property/Locust Grove and west side of the northern parcel. The property is moderately covered with field grasses that were recently swathed. It is surrounded by private property to the north and west and is bounded to the south and east by public roadways. An existing residence, which will be removed at the time of development, is located on the southeast corner of the southern parcel. A wet area (indicated by lush green field grasses approximately 233 feet by 75 presumed to be seepage from an irrigation canal (approximately 3 to 5 feet de) that exists near thewestedge of the northern parcel, was observed during the field exploration. The approximate location of this wet area is shown in Figure 2. SUBSURFACE CONDITIONS We explored the soil and groundwater conditions at the site to depths in the range of approximately 8 to 11 feet by excavating eight test pits on August 16, 2007 with a backhoe subcontracted to GeoEngineers. The locations of the test pits were surveyed by J-U-B Engineers, Inc. and are depicted on Figure 2. General soil conditions are presented below. Details of the field exploration and laboratory testing programs, exploration logs, and lab test results are presented in Appendix A. ,., We encountered topsoil at all test pits. Thickness of topsoil ranged from approximately 6 to 8 inches at the test pits. The topsoil had abundant roots throughout and had recently been plowed. Fine-grained soil was encountered below the topsoil and consisted of silt and clay with varying percentages, up to approximately 15 percent, of sand. In general, these soils were very stiff to hard in - place and dry. The silt and clay soils were encountered to depths down to approximately 3 1/2 feet below existing grade. These fine-grained soils were generally characterized as having low strength, moderate to high compressibility, and low permeability. Coarse -grained soil was encountered below the fine-grained soils. The coarse -grained soil included dense to very dense sand and gravel with variable silt and clay content and some cobbles. We encountered sand to a depth of approximately 5 to 7 feet. The sand was fine- to coarse -grained, dense to . The cementation rveanged from ry dense in M place, and had layers of cementation/caliche at some test pit locations �- weakly to highly cemented. Below approximately 5 to 7 feet, gravel with some cobbles was found interbedded with fine- to medium -grained sand. Below approximately 5 to 7 feet, the coarse -grained soil was characterized by high strength, low to moderate compressibility and moderate to high permeability. We observed moderate to severe caving in all of the test pit sidewalls due to the granular, cohesionless soils below approximately 4.5 to 7 feet in depth. We installed piezometers to the bottom of all test pits at the time of excavation. Groundwater was not observed at the time of excavation on August 16, 2007 nor was groundwater observed in the piezometers on August 30, 2007. File No. 16566-001-00 September 4, 2007 Page 2 GEOENGINEERi�g .. r GENERAL CONCLUSIONS AND RECOMMENDATIONS A summary of the preliminary design and construction considerations for the proposed project is provided below. The summary is presented for introductory purposes only and should be used in conjunction with k the complete discussion in the appropriate sections of this report. • The fine-grained site soils are moisture -sensitive because of the fines (silt- and clay -sized soil particles passing the U.S. No. 200 sieve) content and the plasticity of some of these fines. It will be difficult to properly compact these soils if the moisture content is more than about 2 percent above or below optimum. • Seasonal high groundwater depth is estimated to be on the order 12 feet below existing grade. L" • Infiltration rates are estimated to be very low in fine-grained and cemented soils. Infiltration rates are estimated to be high (8 in./hr.) in the coarse -grained sand and gravel soils generally encountered below approximately 5 to 7 feet in depth at the proposed infiltration sites. A table of �- infiltration rates and depths is provided in the "Stormwater Infiltration Considerations" section of this report. • A wet area (approximately 150 by 150 feet) was observed at existing ground surface near the western edge of the northern parcel. This wet area may be the result of seepage from an existing drainage canal that runs parallel to the west edge of the northern parcel. SITE GRADING Suitability of On -Site Soil The soils encountered in the upper 2 to 3 1/2 feet of all tests pits consisted of fine-grained soils containing clay and silt and are generally not recommended for use as structural fill. We encountered sandy soils below the fine-grained soils to a depth of approximately 5 to7 feet. The sand was fine- to coarse -grained, dense to very dense in place, and had layers of cementation at some test pit locations. The soils encountered below approximately 5 to 7 feet consisted of gravel with fine to medium sand and some cobbles. In general, granular soils encountered below approximately 3 1/2 feet are suitable for use as structural fill, provided they meet the structural fill criteria and are properly moisture conditioned and compacted as recommended below in the "Structural Fill Placement" section. As noted above, the fine- grained soil is moisture sensitive and will be difficult to compact if the moisture content is more than a few percent either wet or dry of optimum. If fine-grained soils are used for structural fill, they will require thorough, uniform moisture conditioning to facilitate compaction as recommended in the following sections. Site Preparation We recommend that the proposed areas to be developed be stripped of all vegetation, topsoil and other deleterious material. We further recommend that roots greater than %2 inch in diameter be grubbed out. We recommend that the site be proofrolled with a heavily loaded truck or loader to identify any areas of soft soil. Proofrolling should be observed by a representative from our firm to assess the adequacy of the subgrade conditions and to identify areas needing remedial work. We recommend that this procedure not be performed during wet weather. If construction needs to continue during wet weather, it m ay be necessary to overexcavate disturbed material and place a layer of select imported fill (sand and gravel File No. 16566-001-00 September 4, 2007 Page 3 GEOENGINEER� k �rr ywith less than 5 percent fines) to provide a working surface over moisture -sensitive soils. Areas of deeper, soft, wet, unstable subgrade that are encountered or created, may require the Contractor to overexcavate and stabilize the subgrade by placing an engineer -approved woven geotextile and clean, G compacted granular fill to create a working platform. Relatively light, non -vibratory compaction equipment should be used during this operation to minimize further softening and pumping of the exposed subgrade. Any soft, loose or otherwise unsuitable areas identified during proofrolling should be recompacted, if practical, or removed to a depth of approximately 2 feet or firm bearing, whichever is less, and replaced with structural fill. The prevailing surficial soils on the site will be moisture -sensitive, difficult to operate on, and very difficult to compact during wet weather. Rubber -tired vehicles will disturb this type of soil when it is above the optimum moisture content. It readily absorbs moisture and is difficult to dry out. It has a moderate erosion potential in -place and is easily transported by running water when disturbed. Therefore, silt fences and other Best Management Practices (BMPs) may be necessary to control erosion and sediment transport during construction. The vegetation and topsoil act as protective layers to the surficial soil. Therefore, they should be removed only where and when necessary. All areas planned for structural fill should first be scarified to a minimum depth of 8 inches, moisture conditioned to within 2 percent of the optimum moisture content, and then compacted to a minimum relative compaction of 90 percent of the maximum dry density (MDD), based on the American Society for Testing and Materials (ASTM) D1557 laboratory test procedure. Structural Fill Criteria k ... On -site and import soils used as structural fill should be non -expansive, reasonably well -graded, and free of organics, other perishable material and construction debris. In addition, they should meet the following criteria. L. Percent Passing Sieve Size (by dry weight) k 4'1 100 #4 70-100 No. 200 0-35 Percent Passing Max. Max. No. 200 Sieve LL pI 0-20 40 15 21-35 35 10 Liquid Limit (LL); Plasticity Index (PI) Min. R-value = 40 (pavement areas only) Structural Fill Placement All new fill and backfill placed under building pads and pavement areas should be placed and compacted as structural fill subsequent to site preparation work as described above. The fill should be placed in horizontal lifts not exceeding 8 inches in loose thickness, or less if necessary, to obtain adequate File No. 16566-001-00 September 4, 2007 Page 4 GEOENGINEERS� compaction. Each lift must be thoroughly and uniformly moisture conditioned and compacted. We recommend that all structural fill placed beneath building pads and pavement subgrade elevation be compacted to at least 95 and 90 percent of the maximum dry density (MDD), respectively, as determined by the ASTM D 1557 test procedure. l.. All structural fill material should be free of organics, debris and other deleterious material, with no individual particles larger than 4 inches in diameter or one-half the lift thickness, whichever is smaller. L. As the amount of fines increases, the soil becomes increasingly sensitive to small changes in moisture content and adequate compaction becomes more difficult to achieve, particularly during wet weather. Generally, soils containing more than about 5 percent fines by weight cannot be properly compacted when the moisture content is more than a few percent from optimum. Sufficient earthwork monitoring and a sufficient number of in -place density tests should be performed to evaluate fill placement and compaction operations and to confirm that the required compaction is being achieved. Imported and on -site structural fill soil should conform to the recommendations provided in the "Structural Fill" section above. We suggest that the fines content be limited to about 30 percent and that the Plasticity Index of such fines be less than 10 for imported fill that will be placed during dry weather L. and on dry subgrade, provided that the moisture content is near optimum to obtain adequate compaction. If structural fill is placed during wet weather or will be reworked during wet weather, we recommend that imported fill be used and consist of well -graded sand and gravel with a fines content limited to 5 percent based on that portion passing the 3/4-inch sieve. DESIGN/CONSTRUCTION CONCERNS L' A wet area (approximately 233 feet by 75 feet) was observed at existing ground surface near the western edge of the northern parcel. The approximate location of this wet area is shown in Figure 2. This wet area may be the result of seepage from an existing drainage canal that exists near the west edge of the northern parcel. In order to prevent distress to structural improvements (e.g., foundations, concrete slab - on -grade, and pavement areas), consideration should be given during project design to diverting this canal water seepage away from structural improvements or sealing the canal to prevent seepage. PDuring construction this wet area may require overexcavation and replacement with structural fill as described in the section "Site Grading". TEMPORARY EXCAVATIONS The Contractor is responsible for the selection, design, construction and maintenance of the shoring method and temporary slopes. Safety requirements established by OSHA or other applicable regulatory agencies shall be followed during excavation and construction by the Contractor. Heavy construction equipment, construction materials, or soil stockpiles should not be located near the top of any excavation. Contractors should anticipate sloughing and caving of excavation sidewalls during excavation due to cohesionless granular soils. File No. 16566-001-00 September 4, 2007 Page S GEOENGINEER� i. STORMWATER INFILTRATION CONSIDERATIONS Depth to Groundwater We installed eight piezometers at the site to measure the depth to groundwater on August 16, 2007. No groundwater was present at the time of excavation or during follow-up groundwater measurements on August 30, 2007. Figure 2 shows the locations of test pits/piezometers that were used to estimate the seasonal high groundwater elevation. Regional groundwater well data available from the Idaho Department of Water Resources (IDWR) for three wells shows that static groundwater levels in the last 10 years range from approximately 12 to 17 feet below the ground surface in the vicinity of this site. The well driller's report for the existing residence located at this site (owner L. Johnson, 1570 East Ustick Road) indicates a static groundwater level in 2002 of 16 feet. Seasonal high groundwater is expected to occur in late summer as a result of irrigation recharge. For design purposes, we recommend an estimated seasonal high groundwater level of approximately 12 feet below existing ground surface. Infiltration Rate The tables below describe the soil conditions encountered, recommended allowable infiltration rate for V. each layer, and our recommendations as to stormwater disposal at the locations of five test pits. These test pits were located in potential infiltration gallery areas. Table 1. Allowable Infiltration Rates t Test Pit Depthr l Type Allowable Infiltration Rate TP-2 % to 2 feetlay _....._.............. _._._..._......_......_.... _.....-_..._..._. _.. -- .A... ......... _._.._..._................. __.._.......__.._..Not suitable for infiltration 2 to 2% feetted sand ._.._.....-----_ _..__.....__.........._.__......_.__.._._.__...._....-_-.._.._........ _._......._.......... Not suitable for infiltration _..........._...._.....__............._...__..._.._._...._._-•-----._............-....—..—........._............... .._........._._..__.-..._......_...__._._.._. __...2% to5% feet y sand 2 inches_Per hour............__. _ 5 % to 6 feetted sandNot suitable for infiltration__.—_.._..._................... 11 feety gravel _.. ... .......to 8 inches per hour Recommendation: Discharge water to silty sand below 2% feet at 2 inches per hour or below 6 feet at 8 inches per hour. Test Pit Depth Soil Type Allowable Infiltration Rate TP-3 % to 2 feet Clay ...-.- .................................... ............ _............_._.._._..._.......__. _. Not suitable for infiltration 2 to 3 feet _....._.._..._.___..._....._._.._..-._ __._. _.__..._._.....-._......_.._. _._.._._.__._.. Cemented sand __._.__._.._.__._.._.. __. . -..--- _. .__.__.._ _......... .. ._..........._.............____- ...__.._.._.__......_.........._................. Not suitable for infiltration _ 3 to 4 feet Cemented sand ..._. ............._...... _ ...._.__...... ____.......................... Not suitable for infiltration 4 to 7 feet Sand .................._.__...._...................._............ --......._..._....._........_... ..... ..........-.._..._.._.......---..........__..... 8 inches per hour 7 to 10 fLeet Sandy gravel _ ..._.._........._........_._..............._.-.__...._.......--- �"'����----•-- 8 inches per hour Recommendation: Discharge water to sand below 4 feet at 8 inches per hour. Lr File No. 16566-001-0o September 4, 2007 Page 6 • GEOENGINEER� Test Pitr2Y2 h Soil Type Allowable Infiltration Rate TP-5feet Clay ...._..._._.—_._._—._._. Not suitable for infiltration __._._—._._._......__. _. —._..—.._........... _..._...__........ _._.. Zo feet Cemented sand.... -.....-__— Not suitable for infiltration ......__._..._....... feet Sandy gravel 8 inches per hour Recommendation: Discharge water to sand below 5% feet at 8 inches per hour. i.r Test Pit TP-6 __........_......_.._ __...__._.. Depth % to 2 feet —. __.__._._......_....__..__._.—. Soil Type Clay __....._._.._....._... _...._....__._..._...._..__._.__. Allowable Infiltration Rate suitable. for infiltration 2 to 3% feet Cemented clay y __..._...__.__...._.....__......---...Not —-._.......... _.:...____ Not suitable for infiltration 3% to 5% feet Sand with silt --____..................... _...... _.... 2 inches per hour — - 5% to 8 feet Sandy gravel ----._._......_.__`... _...... _._..._...—._................ _.—.... -... _... _...... 8 inches per hour Recommendation: Discharge water to sand below 331 feet at 2 inches per hour or below 6 feet at 8 inches per hour. Test Pit Allowable Infiltration Rate Depth Soil T e yP TP-8 % to 2 feet Clay _.._......___.._. _....._._.____...._.._..... r Not suitable for infiltration __.._.._.____.._._.._.._....... ._. 2 to 3 feet ...._.._..___...._ Sand with silt -..... .-._._..—._.._.---.__._..._ ---------- — 2 inches per hour ..._......_._...._.__...._..._...._.—.._.—_.__.._..._._ 3 to 4% feet Sand with clay ..............—._.__.._._.__.._.._...... .:_......_.__.............—__-_.. 2 inches per hour ............... ....... -- L 4% to 9% feet Sandy gravel .... _........ _.-_......._. _..—__.. ——_...._._..._.._._..—_.... _........ -....... _..... __..... 8 inches per hour Recommendation: at 2 inches hour below Discharge water to sand below 2 feet per hour. per or 5 feet at 8 inches The estimated infiltration rates above are based on the soil types encountered and upon the rates provided in the Ada County Highway District (ACHD) Design Manual as well as our judgment They also are based on the assumption that the infiltration system will be designed and onstructedce. in general accordance with ACHD Design Manual recommendations. If another methodology will be used please consult with us to be sure that the infiltration rates above are applicable. 1 �•• Based upon the fine-grained soils at the surface, we do not recommend discharging stormwater at the surface. The discharge needs to be released in the more permeable, non -cemented coarse -grained soils. The soils with the greatest infiltration capability are the sand and sandy gravel that are generally found at approximately 5 Y2 feet and deeper. PAVEMENT RECOMMENDATIONS We obtained a bulk soil sample from test pit TP-1 and performed an R-value test. The R-value test result for the soil sample was 68. Due to the anticipated variability of the soils expected at subgrade elevations, L we have performed the pavement design assuming an R-value of 40. I hw File No. 16566-001-00 September 4, 2007 Wage 7 w GEOE•NGINEERS� The pavement section presented below is recommended for residential `local' and `collector' streets with an average daily traffic (ADT) of less than 2,000 and a traffic index (TI) of 6. Table 2. Recommended Pavement Section for Residential Street r.r Material Min. Thickness (inches) ClassIII Plant Mix 2/_.__._.._...._.._.._..__..__......_...._..._......__.._.__._...__......__....__.._.._........ _ . _. __. _ ._.........._._.._.___....._-.-•---.__._... 3/4-inch, crushed aggregate base _..__._.�._........... ......_..._.__.._...__,--..__..._......_. 4 3-inch minus granular subbase g The thicknesses above are minimum thicknesses for each layer. The materials should meet the requirements specified below. We recommend that the roadway construction be completed in accordance with the current edition of the Idaho Standards for Public Works Construction (ISPWC). The base course should conform to alof l the i specifications for "3/4-inch (Type I) crushed aggregate for base" as described in Section 802 of the ISPWC. The plantmix pavement should conform to all of the specifications for Class III mix as described in Section 810 of the ISPWC. The crushed aggregate base should be compacted to a minimum of 95 percent of MDD per ASTM D 1557. We recommend that the subgrade be prepared in accordance with the recommendations in the "Site Grading" section above. DRAINAGE CONSIDERATIONS am We recommend that the ground surface adjacent to structures and pavement areas be graded to drain surface water away. A minimum slope of 5 percent is recommended for a distance of at least 10 feet (2003 International Building Code, Section 1803.3) from buildings. Foundation and utility trench backfill should be compacted to the requirements discussed above to reduce potential for providing a conduit for surface water. CORROSION POTENTIAL The results of the corrosivity testing (pH, sulfate, resistivity) performed on one soil sample is presented in Table 3 below. Table 3. Corrosivity Testing Results Depth Below LResistivityTest Pit No. Existing Grade (ft) Fi Soluble Sulfatep m-cm) (ppm)TP-1 1 to 3 feet 8.1,600 < 5 Based on the results of the laboratory testing, there is minor potential for sulfate exposure/attack to concrete that comes in contact with native soil. Therefore, a Type II cement is acceptable. The degree of corrosive potential for metals exposed to the native soils is severe. V r File No. 16566-001-00 September 4, 2007 Page 8 GWENGINEER� t r. } LIMITATIONS We have prepared this report for use by RC Meridian Partners, LLC and J-U-B Engineers, Inc. for design I of the proposed Chalet Marseilles Subdivision located north of East Ustick Road and west of North Locust Grove in Meridian, Idaho, as shown in the Vicinity Map, Figure 1. Within the limitations of scope, schedule and budget, our services have been executed in accordance with ►.. generally accepted practices in the field of geotechnical engineering in this area at the time this report was prepared. No warranty or other conditions, express or implied, should be understood. Any electronic form or hard copy of this document (email, text, table, and/or figure), if provided, and any attachments are only a copy of a master document. The master hard copy is stored by GeoEngineers, Inc. and will serve as the official document of record. Please refer to Appendix B titled "Report Limitations and Guidelines for Use" for additional information pertaining to use of this report. We appreciate the opportunity to work with you on this project. If you have any questions regarding this report, or if you need additional information, please call. L L. File No. 16566-001-00 September 4, 2007 Page 9 GEoENGINEER a E 6 O 0 O LO O O O O (0 LO 60 a r m d O m N 0 Partie is Sumer i e,. 9e aa�n— L_ 7 Edgar tiro _ e N,_, -- ` East s rtCc Ronk i° °� � � CD tail � >p. n Sharp - II L � er 7S01Dk o Stormy a __� ee, Karnay - Sedgewick S Finch Creek Cougar Creek Claire - J r 50` _Hawk Wakely _\� l - -0 � Chimere n �! s Creason Latelal Moose`, Hawk <^ o� ' oe m G m — m � — Challis K WWooy . dbur = r ar w Groi " f use / Q) Meadowgrass _ u c F y o �A�� Gtenloch _ I Chr sfietd ar — ,5 - H — Hunter ney Suhlateral { — Blue Heron � c ___ c N o TourmainE f, N CY) y "s Chateau Chateau Q 3: _ _ Notes: 1. The locations of all features shown are approximate. 2. This drawing is for information purposes. It is intended to assist in showing features discussed in an attached document. GeoEngineers, Inc. cannot guarantee the accuracy and content of electronic files. The master file is stored by GeoEngineers, Inc. and will serve as the official record of this communication. 3. It is unlawful to copy or reproduce all or any part thereof, whether for personal use or resale, without permission. Data Sources: Data are from the StreetMap USA. USGS topo map provided by TerraServer (DRG-Scale4m). Idaho State Plane, West (NAD 83) 2,000 0 2,000 FM Feet u c 3 c 3 Z C" L� I 0 0 0 0 (D (D u-) i a a c� i 0 0 0 0 0 cD 07 i Cn 0 m %///'■ j W:�ifWi�rL"•' Legend y TP-2 Test Pit Number and Location Approximate Wet Area Boundary Notes: 1. The locations of all features shown are approximate. 2. This drawing is for information purposes. It is intended to assist in showing features discussed in an attached document. GeoEngineers, Inc. can not guarantee the accuracy and content of electronic files. The master file is stored by GeoEngineers, Inc. and will serve as the official record of this communication. 3. This figure was originally produced in color. Reference: Untitled drawing provided by JUB Engineers, dated 8/7/07 S 200 0 200 mom Feet GEoENGINEERS L�g FIELD EXPLORATION AND LAB APPENDIXA ORA TORY TESTING Mr APPENDIX A FIELD EXPLORATION AND LABORATORY TESTING EXPLORATION PROGRAM { Soil and groundwater conditions at the site were explored using a John Deere 310 backhoe on August 16, .r 2007. A total of eight test pits (TT-1 through TP-8) were completed at the site to depths ranging from approximately 8 to 11 feet deep below existing grade. The locations of the explorations were surveyed by J-U-B Engineers, Inc and are shown in Figure 2. r A representative from our office observed the explorations on a full-time basis, maintained detailed logs, and obtained representative grab samples of the soils encountered for further examination in our laboratory. The soils encountered were classified visually in accordance with the classification system shown in Figure A-1. The logs of the test pits are shown in Figures A-2 through A-9. Each of the soil samples was evaluated in our laboratory to confirm the soil classifications and soil properties described in the logs. LABORATORY TESTING Atterberg Limits Atterberg limits (ASTM D4318-98) were established on four selected samples. Atterberg limits are used primarily for classification and indexing of cohesive, fine-grained soils. The liquid limit (LL) and plastic limit (PL) are defined as the moisture content of a cohesive soil at arbitrarily established limits for liquid and plastic behavior, respectively. The plasticity index (PI) is the difference between the LL and the PL. 6M The results of the Atterberg limits are presented on Figure A-10. I Fines Content The amount of material finer than the U.S. No. 200 sieve (a "No. 200 wash" or "fines content determination") was completed for five soil samples in accordance with ASTM D 1140. The results are presented on the test pit logs. Resistance Value t A resistance value (Idaho Method T-8) was completed on one selected sample from test pit TP-1. Resistance value data is used primarily for estimating bearing strength of soil from a vertically applied load. The result of the resistance value test is presented on Figure A-11. File No. 16566-001-00 PRgeA-1 SeVember4, 2007 GWENGINEERS� SOIL CLASSIFICATION CHART MAJOR DIVISIONS SYMBOLS TYPICAL GRAPH LETTER DESCRIPTIONS CLEAN 0 QO GW WELL -GRADED GRAVELS, GRAVEL - SAND MIXTURES GRAVEL GRAVELS AND O O O O POORLY -GRADED GRAVELS, GRAVELLY (LITTLE OR NO FINES) SOILS Q O O O GP GRAVEL -SAND MIXTURES COARSE GRAINED MORE THAN 50% GRAVELS WITH 0 O GM SILTY GRAVELS, GRAVEL - SAND - SOILS OF COARSE FRACTION FINES SILT MIXTURES RETAINED ON NO. (APPRECIABLE 4 SIEVE AMOUNT OF FINES) GC C CLAYEY GRAVELS, GRAVEL -SAND - O CLAY MIXTURES CLEAN SANDS `SW WELL-GRADEDSANDS, GRAVELLY SANDS MORE THAN 50% SAND RETAINED ON NO. 200 SIEVE AND (LITTLE OR NO FINES) SANDY SP POORLY -GRADED SANDS, SOILS GRAVELLY SAND MORE THAN 50% OF COARSE SANDS WITH �+ SM SILTY SANDS, SAND - SILT FRACTION FINES MIXTURES PASSING NO. 4 SC CLAYEY SANDS, SAND -CLAY SIEVE (APPRECIABLE AMOUNT OF FINES) MIXTURES INORGANIC SILTS, ROCK FLOUR, ML CLAYEY SILTS WITH SLIGHT PLASTICITY SILTS INORGANIC CLAYS OF LOW TO FINE AND LIQUID LIMIT CL MEDIUM PLASTICITY, GRAVELLY GRAINED LESS THAN 50 CLAYS CLAYS, SANDY CLAYS, SILTY CLAYS, LEAN CLAYS SOILS OL ORGANIC SILTSAND ORGANIC SILTY CLAYS OF LOW PLASTICITY MORE THAN 50% PASSING NO. 20D I MH INORGANIC SILTS, MICACEOUS OR SIEVE I I DIATOMACEOUS SILTY SOILS SILTS AND LIQUID LIMIT CH INORGANIC CLAYS OF HIGH CLAYSGREATER THAN 50 z PLASTICITY OH ORGANIC CLAYS AND SILTS OF MEDIUM TO HIGH PLASTICITY HIGHLY ORGANIC SOILS _ _ _ _- PT PEAT, HUMUS, SWAMP SOILS WITH Kin- � HIGH ORGANIC CONTENTS -- ...- r - ......,­ w uUluerl in Or aLai Soil classifications Sampler Symbol Descriptions 2.4-inch I.D. split barrel Standard Penetration Test (SPTJ Shelby tube ® Piston UDirect -Push ® Bulk or grab Blowcount is recorded for driven samplers as the number of blows required to advance sampler 12 inches (or distance noted). See exploration log for hammer weight and drop. A "P" indicates sampler pushed using the weight of the drill rig. ADDITIONAL MATERIAL SYMBOLS SYMBOLS TYPICAL DESCRIPTIONS GRAPH LETTER CC Cement Concrete AC CR TS Asphalt Concrete Crushed Rock/ Quarry Spalls Topsoil/ Forest Duff/Sod Measured groundwater level in _ exploration, well, or piezometer TGroundwater observed at time of _ exploration Perched water observed at time of exploration Measured free product in well or _ piezometer Stratigraphic Contact Distinct contact between soil strata or geologic units /Gradual change between soil strata or geologic units _ _ _ _ Approximate location of soil strata change within a geologic soil unit Laboratory /Field Tests %F Percent fines AL Atterberg limits CA Chemical analysis CID Laboratory compaction test CS Consolidation test DS Direct shear HA Hydrometer analysis MC Moisture content MD Moisture content and dry density OC Organic content PM Permeability or hydraulic conductivity PP Pocket penetrometer SA Sieve analysis TX Triaxial compression UC Unconfined compression VS Vane shear Sheen Classification NS No Visible Sheen SS Slight Sheen MS Moderate Sheen HS Heavy Sheen NT Not Tested NOTE: The reader must refer to the discussion in the report text and the logs of explorations for a proper understanding of subsurtace conditions. Descriptions on the logs apply only at the specific exploration locations and at the time the explorations were made; they are not warranted to be representative of subsurface conditions at other locations or times. KEY TO EXPLORATION LOGS GEOENGINEERS / FIGURER-1 Date Excavated: 08/16/07 Logged by: BWH Equipment: John Deere 310 SG Surface Elevation (ft)� 2603 . z � � U MATERIAL DESCRIPTION o OTHER TESTS iu Ei w m m a m o) s o f AND NOTES O 0 Cn Cn J 6W m M 0 c TS 6 inches topsoil 2 v �, M1- Light brown silt with trace sand (hard, dry) 1 1 2 PP>4.5 tons/fl — CL Light brown clay with sand (hard, moist) R-value 2 2600 3 SP-SC Reddish brown fine to medium sand with clay (dense, dry) 10 %F=76 AL, PI=9, LL=32 4 (Moderately cemented from 4.5 to 5 feet) 5 5 o ° ° GP Reddish brown sandy fine to coarse gravel with cobbles (dense, moist) 6 0 0 0 0 0 0 0 0 o 0 0 0 o 0 0 a o 2595 8 ° 0 0 0 0 0 o 0 0 9 0 0 0 0 0 0 0 \ �- 0 0 0 10 10 Test pit completed at 10 feet No groundwater seepage observed � Moderate caving observed at 6.5 feet w 11 a 0 0 12 z IL 2590 13 , O O 0 14 wNote: 15 15 See Figure A-1 for explanation 0 o a_ of symbols. The depths on the test pit logs are based on an average ofineasurements across the test pit and should be w considered accurate to 0.5 foot. O 3 LOG OF TEST PIT TP-1 ct: Chalet Marseilles Subdivision GMENGINEER 5 ct Location: Meridian, Idaho EProject Number: 16566-001-00 Figure A-2 Sheet 1 of 1 Date Excavated: 08/16/07 Logged by: BWH Equipment: John Deere 310 SG Surface Elevation (ft)- 2603 C E > Z 2 � MATERIAL DESCRIPTION o OTHER TESTS n w w m flU m rn o f _ AND NOTES cn 0 0 6 cn 2v TS 6 inches topsoil _• CL Brown clay with sand (hard dry) PP>4.5 tons/It' 1 1 2 12 AL, PI=17, LL=34 SP White and red fine to medium sand (dense, dry) (strongly cemented, %F=78 SM calcium carbona e veins caliche Reddish brown -Ity fine to medium sand (dense, dry) 2600 3 2 17 %F=42 4 5 5 (Cemented) GP .0 ° 0 0 0 Reddish brown sandy fine to coarse gravel with cobbles (dense, moist) 0 7 0 0 0 0 0 0 0 0 2595 8 0 ° ° 0 0 0 n 0 o 0 9 ° 0 0 0 0 0 � o 0 0 ❑ C7 0 0 0 0 w > w o 0 11 0 Test pit completed at 11 feet No groundwater seepage observed o Moderate caving observed at 6.5 feet 0 0 m co 12 !2 z z 2590 13 0 0 14 F WNote: 15 15 See Figure A-1 for explanation o The depths on the test pit logs are based ofsymbols. on an average of measurements a S2 across the test pit and should be considered accurate to 0.5 foot. O 3 LOG OF TEST PIT TP-2 a E� Chalet Marseilles Subdivision > N G N E E RS 7Project: Project Location: Meridian, Idaho Project Number: 16566-001-00 Figure A-3 Sheet 1 of 1 Date Excavated: 08/16/07 Equipment: John Deere 310 SG Logged by: Surface Elevation 2604 c E z' MATERIAL DESCRIPTION o OTHER TESTS D W 0- a ta Ww 0 °w' F= n2 6 c w 0 AND NOTES mtm 0 0 uJ U of C7 cq o 0 TS 6 inches topsoil U PP>4.5 tons/fie Light brow�l clay with trace sand (hard, dry) 1 I 2 SP Light brown fine to medium sand with trace silt (dense, dry) (cemented, 2 calcium carbonate veins) 3 SP Light reddish brown fine to medium sand with trace clay (dense, dry) 3 •2600 4 (Moderately cemented from 3.5 to 4 feet) 5 5 6 7 0 o 0 GP Reddish brown and white sandy fine to coarse gravel with cobbles co 0 (dense, moist) 0 0 8 0 0 0 0 0 0 0 ?595 9 0 0 0 0 0 0 0 0 0 10 10 0 0 Test pit completed at 10 f t ee No groundwater seepage observed 11 Moderate caving observed at 6 feet 12 13 590 14 15 15 Note: See Figure A-1 for explanation of symbols. The depths on the test pit logs are based on an average of measurements across the test pit and should be considered accurate to 0.5 foot. LOG OF TEST PIT TP-3 Project: Chalet Marseilles Subdivision M N G I N E E;R Project Location: Meridian, Idaho Project Number: 16566-001-00 Figure A-4 Sheet 1 of 1 Date Excavated: 08/16/07 Logged by: B WH Equipment: John Deere 310 SG Surface Elevation (ft)7 2604 E w MATERIAL DESCRIPTION OTHER TESTS °) a�i a> Q o WQ? ��2 n mom s of AND NOTES m a) Cn 0 0 C:i (n y C TS 6 inches topsoil 2i U C- Light brown clay with f ace sand (hard dry) PP>4.5 tons/if 1 2 SP-SC Light brown fine to coarse sand with clay (dense, dry) (cemented, t calcium carbonate veins) 3 SM Reddish brown silty sand (dense, dry) 2 2600 4 5 5 Cemente calcium carbonate veins 0 0 0 GP Reddish brown sandy gravel with cobbles (dense, 6 moist) 0 o 0 0 0 3 0 0 0 o 0 0 0 o 0 0 0 0 $ 0 0 0 0 0 0 n 0 0 0 2595 9 0 0 0 0 0 0 o M 0 o 0 10 10 0 Test pit completed at 10 feet No groundwater seepage observed � Moderate caving observed at 6 feet w 11 � C7 a L7 0 0 0 0 m 12 a z 13 0 0 0 7 2590 14 77 N — W 15 15 Note: See Figure A-1 for explanation _ o o' of symbols. The depths on the test pit logs are based on an average of measurements a Ln across the test pit and should be considered accurate to 0.5 foot. O - 3 LOG OF TEST PIT TP-4 Project: Chalet Marseilles Subdivision W N G E E R �Ao*'^ Project Location: Meridian, Idaho Project Number: 16566-001-00 Figure A-5 Sheet 1 of 1 Date Excavated: 08/16/07 Equipment: John Deere 310 SG 3 LUU QF TEST PIT TP-5 �^ Project: Chalet Marseilles Subdivision n V Eo N G I N E E R j Project Location: Meridian, Idaho Project Number: 16566-001-00 Figure A-6 Sheet 1 of 1 Logged by: BWH Surface Elevation (ft)7 2605 Date Excavated: 08/16/07 — Logged by: B" Equipment: John Deere 310 SG Surface Elevation (ft): 2605 a> � Q�� Z N V MATERIAL DESCRIPTION c OTHER TESTS — w 0� E E m O o E AND NOTES 2605 0 fn VJ C9 J " C U) 0 TS 6 inches topsoil CL Brown clay with trace sand (hard dry) PP>4.5 tons/& 1 1 — 2 Reddish brown clay with trace sand (hard dry) (slightly cemented calcium carbonate veins) (fine roots) PP>4.5 tons/ftZ 3 Z (Cemented) SP-SM Reddish brown fine to medium sand with silt (dense, dry) 4 3 2660 5 000 GP Reddish brown sandy fine to coarse gravel with cobbles (dense, moist) 0 0 .., 6 0 0 0 0 0 0 — 0 0 0 7 0 0 0 0 0 0 0 0 0 8 Test pit completed at 8 feet No groundwater seepage observed Severe caving observed at 5.5 feet 9 0 M — m 2585 10 c� > 11 w CD a C7 d 12 0 0 co c0 a 13 z LL O O 0 14 25Q0 15 — w Note: See Figure A-1 for explanation of symbols. o The depths on the test pit logs are based on an average of measurements _ a across the test pit and should be considered accurate to 0.5 foot. O — LOG OF TEST PIT TP-6 Project: Chalet Marseilles Subdivision Eo N G I N E E R S leo Project Location: Meridian, Idaho Project Number: 16566-001-00 Figure A-7 Sheet 1 of 1 Date Excavated: 08/16/07 Logged by: BWH IEquipment: John Deere 310 SG Surface Elevation (ft)� 2607 Date Excavated: 08/16/07 Equipment: John Deere 310 SG Logged by: BWH Surface Elevation (ft): 2607 LOG OF TEST PIT TP-8 Project: Chalet Marseilles Subdivision GEoENGINEERS Project Location: Meridian, Idaho ' Figure A-9 Project Number: 16566-001-00 Sheet 1 of 1 aI 5 41 CL 20 10 0 0 0 �- +U 60 80 100 Liquid Limit Job Number: 16566-001-00 Exploration No. Sample Moisture Liquid Plasticity Soil Percent Chart Depth Content Limit Index Description Fines Symbol TP-1 2-3' 10% 32 9 CL, Clay with Sand 76 TP-2 1-2' 12% 34 17 CL, Clay with Sand 78 0 TP-5 .5-1.5' 8% 33 11 CL, Clay with Sand 82 ❑ p TP-7 .5-1.5' 21% 37 14 CL, Clay with Sand 77 X m c° Cb "J'GWENGINEERS CO Atterberg Limits Test Results Figure A-10 n O W N W O 2 J m n R-VALUE IDAHO T-8 Project: RC -Meridian Client: GEO Engineers Lab Number: 1371-2298 Sample ID: Subgrade Soil File Name: GEOE01- BM07420 Date Sampled: 8/20/07 Location: TP-1 @ 1' - 3' Sampled by: Client Soil Description: Silty Sand with Cementation Date Received: 8120/07 Tested by: CAK/Strata R VALUE DATA Percolation: None Polntl Polnt2 Polnt3 SOIL CONSTANTS Exudatinn pcl I - . _ I R VALUE: 68 0 v o o� rn GRADATION: AASHTO T-11, T27 c4i tt) o SCREEN SIZE AS RECEIVED AS TESTED %PASSING %PASSING (� O 8 Co 4" s3" o x ri 0 0 2" n 1" � d a N o0 314" � m m 1/2" N m O � N 3/6" D_ N o o 6 m d c No.4 100 100 c 2 No. B a0. Lq o 16 No.16 o Lti `r No.30 0 o No.50 c o o Cl) No. 100 No. 200 O O O N O O O O ID CD M W O C.0 In VO' M N O O O lue Note: This report covers only mate al as represented soil from this layer or source. by this sample and does not necessarily cover all Reviewed by: -d4ZZ �4, —Wx1 "-""' -r FR c"%.&mr orres:a�r.:a. c�xmcEacyc.� zc';sxxtcnta :esw.s ..1.tfc�rFfy lrra.wt-h.«�::{rxs:nta� v� m I Reference: Laboratory testing performed by STRATA, Inc. GMENGINEERS REPORT L,imiTATIONS AND GUIDELINES FOR USE ..=_.o ..._ � . APPENDIX B REPORT LIMITATIONS AND GUIDELINES FOR USE' This appendix provides information to help you manage your risks with respect to the use of this report. GEOTECHNICAL SERVICES ARE PERFORMED FOR SPECIFIC PURPOSES, PERSONS AND PROJECTS ' This report is for the use by RC Meridian Partners, LLC and J-U-B Engineers, Inc. for design of the L proposed Chalet Marseilles Subdivision project located north of East Ustick Road and west of North Locust Grove in Meridian, Idaho, as shown in the Vicinity Map, Figure 1. This report is not intended for use by others, and the information contained herein is not applicable to other sites. GeoEngineers structures our services to meet the specific needs of our clients. For example, a geotechnical or geologic study conducted for a civil engineer or architect may not fulfill the needs of a construction contractor or even another civil engineer or architect that are involved in the same project. Because each geotechnical or geologic study is unique, each geotechnical engineering or geologic report is unique, prepared solely for the specific client and project site. No one except RC Meridian Partners, LLC and J-U-B Engineers, Inc. should rely on this report without first conferring with GeoEngineers. L• This report should not be applied for any purpose or project except the one originally contemplated. LA GEOTECHNICAL ENGINEERING OR GEOLOGIC REPORT IS BASED ON A UNIQUE SET OF PROJECT -SPECIFIC FACTORS This report --has been prepared for the proposed Chalet Marseilles Subdivision project. GeoEngineers considered a number of unique, project -specific factors when establishing the scope of services for this project and report. Unless GeoEngineers specifically indicates otherwise, do not rely on this report if it L was: • not prepared for you, • not prepared for your project, • not prepared for the specific site explored, or L • completed before important project changes were made. For example, changes that can affect the applicability of this report include those that affect: • the function of the proposed structure; • elevation, configuration, location, orientation or weight of the proposed structure; • composition of the design team; or • project ownership. If important changes are made after the date of this report, GeoEngineers should be given the opportunity to review our interpretations and recommendations and provide written modifications or confirmation, as appropriate. 1 Developed based on material provided by ASFE, Professional Firms Practicing in the Geosciences; www.asfe.org. L File No. 16566-001-00 Page B-1 GWENGINEER LSeptember 4, 2007 SUBSURFACE CONDITIONS CAN CHANGE This geotechnical or geologic report is based on conditions that existed at the time the study was performed. The findings and conclusions of this report may be affected by the passage of time, by manmade events such as construction on or adjacent to the site, or by natural events such as floods, earthquakes, slope instability or groundwater fluctuations. Always contact GeoEngineers before applying a report to determine if it remains applicable. MOST GEOTECHNICAL AND GEOLOGIC FINDINGS ARE PROFESSIONAL OPINIONS Our interpretations of subsurface conditions are based on field observations from widely spaced sampling locations at the site. Site exploration identifies subsurface conditions only at those points where subsurface tests are conducted or samples are taken. GeoEngineers reviewed field and laboratory data and then applied our professional judgment to render an opinion about subsurface conditions throughout the site. Actual subsurface conditions may differ, sometimes significantly, from those indicated in this report. Our report, conclusions and interpretations should not be construed as a warranty of the subsurface conditions. GEOTECHNICAL ENGINEERING REPORT RECOMMENDATIONS ARE NOT FINAL Do not over -rely on the preliminary construction recommendations included in this report. These recommendations are not final, because they were developed principally from GeoEngineers' professional judgment and opinion. GeoEngineers' recommendations can be finalized only by observing actual subsurface conditions revealed during construction. GeoEngineers cannot assume responsibility or liability for this report's recommendations if we do not perform construction observation. Sufficient monitoring, testing and consultation by GeoEngineers should be provided during construction to confirm that the conditions encountered are consistent with those indicated by the explorations, to provide recommendations for design changes should the conditions revealed during the work differ from those anticipated, and to evaluate, whether or not earthwork activities are completed in accordance with our recommendations. Retaining GeoEngineers for construction observation for this project is the most effective method of managing the risks associated with unanticipated conditions. A GEOTECHNICAL ENGINEERING REPORT OR GEOLOGIC REPORT COULD BE SUBJECT TO MISINTERPRETATION Misinterpretation of this report by other design team members can result in costly problems. You could lower that risk by having GeoEngineers confer with appropriate members of the design team after submitting the report. Also retain GeoEngineers to review pertinent elements of the design team's plans and specifications. Contractors can also misinterpret a geotechnical engineering or geologic report. Reduce that risk by having GeoEngineers participate in pre -bid and preconstruction conferences, and by providing construction observation. DO NOT REDRAW THE EXPLORATION LOGS Geotechnical engineers and geologists prepare final boring and testing logs based upon their interpretation of field logs and laboratory data. To prevent errors or omissions, the logs included in a geotechnical engineering or geologic report should never be redrawn for inclusion in architectural or other design drawings. Only photographic or electronic reproduction is acceptable, but recognize that separating logs from the report can elevate risk. File No. 16566-001-00 Page B-2 GWENGINEERS� September 4, 2007 GIVE CONTRACTORS A COMPLETE REPORT AND GUIDANCE Some owners and design professionals believe they can make contractors liable for unanticipated subsurface conditions by limiting what they provide for bid preparation. To help prevent costly problems, give contractors the complete geotechnical engineering or geologic report, but preface it with a clearly written letter of transmittal. In that letter, advise contractors that the report was not prepared for purposes of bid development and that the report's accuracy is limited; encourage them to confer with GeoEngineers and/or to conduct additional study to obtain the specific types of information they need or prefer. A pre - bid conference can also be valuable. Be sure contractors have sufficient time to perform additional study. Only then might an owner be in a position to give contractors the best information available, while requiring them to at least share the financial responsibilities stemming from unanticipated conditions. Further, a contingency for unanticipated conditions should be included in your project budget and schedule. CONTRACTORS ARE RESPONSIBLE FOR SITE SAFETY ON THEIR OWN CONSTRUCTION PROJECTS Our geotechnical recommendations are not intended to direct the contractor's procedures, methods, schedule or management of the work site. The contractor is solely responsible for job site safety and for managing construction operations to minimize risks to on -site personnel and to adjacent properties. READ THESE PROVISIONS CLOSELY Some clients, design professionals and contractors may not recognize that the geoscience practices (geotechnical engineering or geology) are far less exact than other engineering and natural science disciplines. This lack of understanding can create unrealistic expectations that could lead to disappointments, claims and disputes. GeoEngineers includes these explanatory "limitations" provisions in our reports to help reduce such risks. Please confer with GeoEngineers if you are unclear how these "Report Limitations and Guidelines for Use" apply to your project or site. GEOTECHNICAL, GEOLOGIC AND ENVIRONMENTAL REPORTS SHOULD NOT BE INTERCHANGED The equipment, techniques and personnel used to perform an environmental study differ significantly from those used to perform a geotechnical or geologic study and vice versa. For that reason, a geotechnical engineering or geologic report does not usually relate any environmental findings, conclusions or recommendations; e.g., about the likelihood of encountering underground storage tanks or regulated contaminants. Similarly, environmental reports are not used to address geotechnical or geologic concerns regarding a specific project. File No. 16566-001-00 Page B-3 GMENGINEERS� September 4, 2007