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HomeMy WebLinkAbout20092213.tiff • • • GEOTECHNICAL ENGINEERING REPORT RESIDENCE AND SEPTIC SYSTEM 14259 HIGHWAY 392 WELD COUNTY, COLORADO TERRACON PROJECT NO. 21055043 July 22, 2005 Prepared for: • Mr. Matt Green do Green/Coffman Inc. 3620 West 10th Street Greeley, Colorado 80634-1821 Prepared by: Terracon 1289 First Avenue Greeley, Colorado 80631 Telephone (970) 351-0460 Fax (970) 353-8639 EXHIBIT I S llerraron 2009-2213 lierracon • July 22, 2005 Consulting Engineers&Scientists Terracon Consultants, Inc. 1289 First Avenue Mr. Matt Green Greeley, Colorado 80631 Phone 970.351.0460 do Green/Coffman, Inc. Fax 970.353.8639 3620 West 10th Street vnvw.terracon.com Greeley, Colorado 80634-1821 Attn: Mr. Matt Green Re: Geotechnical Engineering Report Residence and Septic System 14259 Highway 392 —Weld County, Colorado Terracon Project No. 21055043 Terracon has completed a geotechnical engineering exploration for the proposed residence and septic system to be located at 14259 Highway 392 in Weld County, Colorado. This study was performed in general accordance with our proposal number P2105047g dated July 1, 2005. The results of our engineering study, including the boring location diagram, laboratory test results, test boring records, and the geotechnical recommendations needed to aid in the design and • construction of foundations and other earth connected phases of this project are attached. We appreciate being of service to you in the geotechnical engineering phase of this project, and are prepared to assist you during the construction phases as well. If you have any questions concerning this report or any of our testing, inspection, design and consulting services, please do not hesitate to contact us. Sincerely, TERRACON • yap- Andrei Bedoya, E.I. Ty G. Alexander, P.E: Staff Engineer Office Manager/Geotechnical Engineer Copies to: Addressee (3) • Delivering Success for Clients and Employees Since 1965 More Than 70 Offices Nationwide • TABLE OF CONTENTS Page No. Letter of Transmittal INTRODUCTION 1 PROPOSED CONSTRUCTION 1 SITE EXPLORATION 2 Field Exploration 2 Laboratory Testing 2 SITE CONDITIONS 3 Soil Conditions 3 Field and Laboratory Test Results 3 Groundwater Conditions 4 ENGINEERING ANALYSES AND RECOMMENDATIONS 4 Geotechnical Considerations 4 Foundation Systems 5 Basement Construction 5 • Lateral Earth Pressures 6 Seismic Considerations 7 Floor Slab Design and Construction 7 Septic System Construction 7 Earthwork 9 General Considerations 9 Site Preparation 9 Fill Materials and Placement 10 Excavation and Trench Construction 10 Additional Design and Construction Considerations 11 Underground Utility Systems 11 Surface Drainage 11 GENERAL COMMENTS 12 APPENDIX A Boring Location Plan Logs of Borings APPENDIX B Laboratory Test Results APPENDIX C General Notes Unified Soil Classification • • GEOTECHNICAL ENGINEERING REPORT RESIDENCE AND SEPTIC SYSTEM 14259 HIGHWAY 392 WELD COUNTY, COLORADO TERRACON PROJECT NO. 21055043 JULY 22, 2005 INTRODUCTION This report contains the results of our geotechnical engineering exploration for the proposed residence and septic system to be located at 14259 Highway 392 in Weld County, Colorado. The purpose of these services is to provide information and geotechnical engineering recommendations relative to: • subsurface soil conditions • groundwater conditions • • foundation design and construction • basement construction • lateral earth pressures • floor slab design and construction • septic systems • earthwork • drainage The recommendations contained in this report are based upon the results of field and laboratory testing, engineering analyses, and experience with similar soil conditions, structures and our understanding of the proposed project. PROPOSED CONSTRUCTION Terracon understands the site is to be developed with a single family 5 bedroom residence with a basement. The residence will also serve as a daycare facility. Additional development of the site will include the construction of a septic system. Structural loads for the proposed residence were not provided, however, Terracon assumes wall and column loads will not exceed 3 kips per lineal foot and 40 kips, respectively. Site grading plans were not provided, however, cuts and fills at the site are anticipated to be minimal. Geotechnical Engineering Report • Residence and Septic System 14259 Highway 392—Weld County, Colorado Terracon Project No. 21055043 Terracon SITE EXPLORATION The scope of the services performed for this project included a site reconnaissance by a Terracon representative, a subsurface exploration program, laboratory testing and engineering analyses. Field Exploration Three test borings were drilled on July 11, 2005. The borings were drilled to approximate depths of 8 to 15 feet at the locations shown on the Boring Location Diagram, Appendix A. Two borings were drilled within the anticipated footprint of the proposed residence. One (1) soil profile boring and six (6) percolation test holes were drilled in the location of the proposed septic system. Percolation tests were conducted in general accordance with Weld County requirements. All borings were advanced with a truck-mounted drilling rig utilizing 4-inch diameter solid stem augers. The borings were located in the field by the client. Ground surface elevations at each boring location were obtained by measurements with an engineer's level from a temporary bench mark (TBM) shown on the Boring Location Diagram. The accuracy of boring locations and elevations should only be assumed to the level implied by the methods used to determine each. • Lithologic logs of each boring were recorded by the field representative during the drilling operations. At selected intervals, samples of the subsurface materials were taken by driving split-spoon and ring- barrel samplers. Penetration resistance measurements were obtained by driving the split-spoon and ring-barrel samplers into the subsurface materials with a 140-pound hammer falling 30 inches. The penetration resistance value is a useful index in estimating the consistency, relative density or hardness of the materials encountered. Groundwater conditions were evaluated in each boring at the time of site exploration, and one day after completion of drilling. Laboratory Testing All samples retrieved during the field exploration were returned to the laboratory for observation by the project geotechnical engineer and were classified in accordance with the Unified Soil Classification System described in Appendix C. At that time, the field descriptions were confirmed or modified as necessary and an applicable laboratory testing program was formulated to determine engineering properties of the subsurface materials. Boring logs were prepared and are presented in Appendix A. • 2 • Geotechnical Engineering Report Residence and Septic System 14259 Highway 392—Weld County, Colorado Terracon Project No. 21055043 Terracon Laboratory tests were conducted on selected soil samples and are presented on the boring logs and in Appendix B. The test results were used for the geotechnical engineering analyses, and the development of foundation and earthwork recommendations. All laboratory tests were performed in general accordance with the applicable local or other accepted standards. Selected soil samples were tested for the following engineering properties: • Water Content • Dry Density • Consolidation/Expansion SITE CONDITIONS The site was located in an agricultural area and was undeveloped at the time of our site visit. The site was relatively flat, however, surface drainage appeared to slope gently to the northwest. Native weeds • and grasses vegetated the site. An irrigation canal was observed about 100 to 125 north of the proposed building area. The site was bordered to the north by agricultural land and the irrigation canal, to the east by a residence, to the south by Highway 392, and to the west by a pet ranch. SUBSURFACE CONDITIONS Soil Conditions As presented on the Logs of Boring, surface soils to depths of 15 feet consisted of clayey sand and sandy lean clay. Field and Laboratory Test Results Field test results indicate that the clay soils vary from medium stiff to stiff in consistency. The sand soils are loose in relative density. Laboratory test results indicate that subsoils at shallow depth are non-expansive. Percolation Test Results Percolation testing conducted in the area of the proposed soil absorption bed are summarized as follows: • 3 • • • Geotechnical Engineering Report Residence and Septic System 14259 Highway 392—Weld County,Colorado Terracon Project No. 21055043 Terracon Percolation Test Results Test Hole Depth Soil Percolation Rate (inches) Classification (minutes/inch) P-1 30 CL 27 P-2 30 CL 18 P-3 30 CL 30 P-4 30 CL 15 P-5 30 CL 11 P-6 30 CL 17 Average 20 Field test results indicate the soils in the area of the proposed septic system have percolation characteristics suitable for standard septic system construction. Groundwater Conditions Groundwater was encountered at approximate depths of 5 to 7 feet in the test borings at the time of • field exploration. When checked one days after the drilling, groundwater was measured at approximate depths of 5 to 6 feet. These observations represent groundwater conditions at the time of the field exploration, and may not be indicative of other times, or at other locations. Groundwater levels can be expected to fluctuate with varying seasonal and weather conditions.. ENGINEERING ANALYSES AND RECOMMENDATIONS Geotechnical Considerations Based on the geotechnical engineering analyses, subsurface exploration and laboratory test results, it is our opinion that the proposed residence may be supported on a spread footing foundation system bearing a minimum of 3 feet above groundwater. Site grade will need to be elevated with fill if a full basement is considered. Slab on grade may be utilized for the interior floor system provided that care is taken in the placement and compaction of the subgrade soil. On-site soils should be suitable for use as engineered fill beneath the foundation systems and floor slabs. Design and construction recommendations for foundation systems and other earth connected phases of the project are outlined below. 0 4 • Geotechnical Engineering Report Residence and Septic System 14259 Highway 392—Weld County, Colorado Terracon Project No. 21055043 Terracon Foundation Systems Due to the properties of the on-site soils and anticipated loading conditions, spread footing foundations bearing upon undisturbed subsoils and/or engineered fill appear suitable for support for the proposed residence. The footings may be designed for a maximum net allowable bearing pressure of 1,500 psf (pounds per square foot). The design bearing pressure applies to dead loads plus design live load conditions. Exterior footings should be placed a minimum of 30 inches below finished grade for frost protection and to provide confinement for the bearing soils. Interior footings in heated areas should be placed a minimum of 18 inches below finished grade. Finished grade is the lowest adjacent grade for perimeter footings. Footings should be proportioned to reduce differential foundation movement. Proportioning on the basis of equal total movement is recommended; however, proportioning to relative constant dead-load pressure will also reduce differential movement between adjacent footings. Total movement resulting from the assumed structural loads is estimated to be on the order of 1 inch or less. Additional • foundation movements could occur if water from any source infiltrates the foundation soils; therefore, proper drainage should be provided in the final design and during construction. Foundations walls should be reinforced as necessary to reduce the potential for distress caused by differential foundation movement. Foundation excavations should be observed by the geotechnical engineer. If the soil conditions encountered differ significantly from those presented in this report, supplemental recommendations will be required. Basement Construction Groundwater was encountered on the site at a depth of 5 feet below existing grade. Full-depth basement construction is considered feasible on the site provided that basement subgrade is a minimum of 3 feet above groundwater level. Site grade will need to be elevated with fill if a full basement is considered. To reduce the potential for groundwater to enter the basement of the structure, installation of a dewatering system is recommended. The dewatering system should, at a minimum, include an underslab gravel drainage layer sloped to an interior perimeter drainage system. The drainage system should consist of a properly sized perforated pipe, embedded in free-draining gravel, placed in a trench at least 12-inches in width. The trench should be inset from the interior edge • of the nearest foundation a minimum of 12-inches. In addition, the trench should be located such that 5 • Geotechnical Engineering Report Residence and Septic System 14259 Highway 392—Weld County, Colorado Terracon Project No. 21055043 Terracon an imaginary line extending downward at a 45-degree angle from the foundation does not intersect the nearest edge of the trench. Gravel should extend a minimum of 3-inches beneath the bottom of the pipe. The drainage system should be sloped at a minimum 1/8 inch per foot to a suitable outlet, such as a sump and pump system. The underslab drainage layer should consist of a minimum 8-inch thickness of free-draining gravel meeting the specifications of ASTM C33, Size No. 57 or 67. Lateral Earth Pressures For soils above any free water surface, recommended equivalent fluid pressures for unrestrained foundation elements are: • Active: Cohesive soil backfill (on-site clay) 45 psf/ft • Passive: Cohesive soil backfill (on-site clay) 250 psf/ft • • Coefficient of base friction 0.35* *The coefficient of base friction should be reduced to 0.30 when used in conjunction with passive pressure. Where the design includes restrained elements, the following equivalent fluid pressures are recommended: • At rest: Cohesive soil backfill (on-site clay) 65 psf/ft The lateral earth pressures herein do not include any factor of safety and are not applicable for submerged soils/hydrostatic loading. Additional recommendations may be necessary if submerged conditions are to be included in the design. Fill against foundation walls should be compacted to densities specified in Earthwork. Compaction of each lift adjacent to walls should be accomplished with hand-operated tampers or other lightweight compactors. Overcompaction may cause excessive lateral earth pressures which could result in wall movement. • 6 • Geotechnical Engineering Report Residence and Septic System • 14259 Highway 392—Weld County, Colorado Terracon Project No. 21055043 Terracon Seismic Considerations The project site is located in Seismic Risk Zone I of the Seismic Zone Map of the United States as indicated by the 1997 Uniform Building Code. Based upon the nature of the subsurface materials, Soil Profile Type "SD" should be used for the design of structures for the proposed project (1997 Uniform Building Code, Table No. 16-J). A site classification "D" should be used for the design of structures for the proposed project (2000 International Building Code, Table No. 1615.1.1). Floor Slab Design and Construction Some differential movement of a slab-on-grade floor system is possible should the subgrade soils become elevated in moisture content. To reduce potential slab movements, the subgrade soils should be prepared as outlined in the earthwork section of this report. Additional floor slab design and construction recommendations are as follows: • Positive separations and/or isolation joints should be provided between slabs and all • foundations, columns or utility lines to allow independent movement. • Control joints should be provided in slabs to control the location and extent of cracking. • Interior trench backfill placed beneath slabs should be compacted in accordance with recommended specifications outlined below. • A minimum 8-inch layer of free-draining gravel should be placed beneath basement floor slabs in conjunction with the underslab drainage system. • Floor slabs should not be constructed on frozen subgrade. • Other design and construction considerations, as outlined in the ACI Design Manual, Section 302.1R are recommended. Septic System Construction Field test results indicate that a standard septic system and leach field (soil absorption bed) is feasible for construction on the site at the location of percolation test holes P-1 through P-6. The system should be designed in accordance with applicable state and county requirements and should be • 7 • Geotechnical Engineering Report Residence and Septic System 14259 Highway 392—Weld County, Colorado Terracon Project No. 21055043 Terracon located at the minimum distances from all pertinent ground features described in Weld County regulations. An average percolation rate of 20 minutes per inch is recommended for design purposes. Groundwater was encountered in the soil profile boring, located at the proposed soil absorption bed, at a depth of 6 feet. Accordingly, the bottom of the leach field should be constructed a minimum of 4 feet above groundwater. Additional design criteria for septic system construction are as follows: • Based upon the proposed residence containing 5 bedrooms, the proposed soil absorption bed should include a minimum of 1,410 square feet of trench in plan view. • A minimum 1,500-gallon capacity septic tank should be used in the design and construction. • Distribution lines within the soil absorption bed should consist of 3- or 4-inch diameter perforated plastic or similar pipe approved in governing regulations. Distribution lines • should be placed the full length of the proposed absorption bed or trench and should not exceed 100-feet in length. Distribution lines should be spaced at a maximum of 6 feet on center with the perimeter lines placed within 3 feet of all sides in the absorption bed. • Absorption beds should be backfilled with a minimum 12 inch thickness of clean graded gravel ranging in size from 3/4 to 2-1/2 inches in diameter. The gravel should extend a minimum of 6 inches below and 2 inches above the distribution pipes. • The gravel bed should be completely covered with untreated building paper prior to final soil cover. Final soil cover should be a minimum of 12 inches in thickness and suitable for vegetative growth. The surface of the soil cover should be graded for positive surface drainage and to reduce the possibility of surface water infiltration. • A gravelless soil absorption bed, or infiltrator system, may also be considered as an alternative to the standard type gravel system outlined above. Terracon understands Weld County allows for a 50% reduction of the leach field size for infiltrator systems. Accordingly, the infiltrator system should consist of a minimum of 46 chambers with infiltrator rows spaced at a minimum 3'/z feet on center. 8 • Geotechnical Engineering Report Residence and Septic System 14259 Highway 392—Weld County, Colorado Terracon Project No. 21055043 Terracon Earthwork General Considerations The following presents recommendations for site preparation, excavation, subgrade preparation and placement of engineered fills on the project. All earthwork on the project should be observed and evaluated by Terracon. The evaluation of earthwork should include observation and testing of engineered fill, subgrade preparation, foundation bearing soils, and other geotechnical conditions exposed during the construction of the project. Site Preparation Strip and remove existing vegetation, debris, and other deleterious materials from proposed building and pavement areas. All exposed surfaces should be free of mounds and depressions which could prevent uniform compaction. Subgrade soils beneath proposed interior and exterior slabs, as well as all exposed areas which will • receive fill, once properly cleared where necessary, should be scarified to a minimum depth of 8 inches, conditioned to near optimum moisture content, and compacted. Although evidence of fills or underground facilities such as septic tanks, cesspools, basements, and utilities was not observed during the site reconnaissance, such features could be encountered during construction. If unexpected fills or underground facilities are encountered, such features should be removed and the excavation thoroughly cleaned prior to backfill placement and/or construction. It is anticipated that excavations for the proposed construction can be accomplished with conventional earthmoving equipment. Depending upon depth of excavation and seasonal conditions, groundwater may be encountered in excavations on the site. Pumping from sumps may be utilized to control water within excavations. Based upon the subsurface conditions determined from the geotechnical exploration, subgrade soils exposed during construction a minimum of 3 feet above groundwater are anticipated to be relatively stable. However, the stability of the subgrade may be affected by precipitation, repetitive construction traffic or other factors. If unstable conditions develop, workability may be improved by scarifying and drying. The individual contractor(s) is responsible for designing and constructing stable, temporary • excavations as required to maintain stability of both the excavation sides and bottom. All excavations 9 • • Geotechnical Engineering Report • Residence and Septic System 14259 Highway 392—Weld County, Colorado Terracon Project No. 21055043 Terracon should be sloped or shored in the interest of safety following local, and federal regulations, including current OSHA excavation and trench safety standards. Fill Materials and Placement Clean on-site soils or approved imported materials may be used as fill material. Imported soils (if required) should conform to the following: Percent fines by weight Gradation (ASTM C136) 3" 100 No. 4 Sieve 70-100 No. 200 Sieve 50 (max) • Liquid Limit 30 (max) • Plasticity Index 15 (max) • Engineered fill should be placed and compacted in horizontal lifts, using equipment and procedures that will produce recommended moisture contents and densities throughout the lift. Recommended compaction criteria for engineered fill materials is 95% of maximum dry density as determined by the standard Proctor method ASTM D698. On-site clay soils should be compacted within a moisture content range of 2 percent below to 2 percent above optimum unless modified by the project geotechnical engineer. Excavation and Trench Construction Excavations into the on-site soils will encounter a variety of conditions, including caving soils and possibly groundwater. The individual contractor(s) should be made responsible for designing and constructing stable, temporary excavations as required to maintain stability of both the excavation sides and bottom. All excavations should be sloped or shored in the interest of safety following local, and federal regulations, including current OSHA excavation and trench safety standards. The soils to be penetrated by the proposed excavations may vary significantly across the site. The preliminary soil classifications are based solely on the materials encountered in widely spaced exploratory test borings. The contractor should verify that similar conditions exist throughout the proposed area of excavation. If different subsurface conditions are encountered at the time of • 10 • • • Geotechnical Engineering Report Residence and Septic System 14259 Highway 392—Weld County, Colorado Terracon Project No. 21055043 Terracon construction, the actual conditions should be evaluated to determine any excavation modifications necessary to maintain safe conditions. As a safety measure, it is recommended that all vehicles and soil piles be kept to a minimum lateral distance from the crest of the slope equal to no less than the slope height. The exposed slope face should be protected against the elements. Additional Design and Construction Considerations Underground Utility Systems All piping should be adequately bedded for proper load distribution. It is suggested that clean, graded gravel compacted to 75 percent of Relative Density ASTM D4253 be used as bedding. Where utilities are excavated below groundwater, temporary dewatering will be required during excavation, pipe placement and backfilling operations for proper construction. Utility trenches should be excavated on safe and stable slopes in accordance with OSHA regulations as discussed above. Backfill should consist of the on-site soils. The pipe backfill should be compacted to a minimum of 95 percent of Standard Proctor Density ASTM D698. • All underground piping within or near the proposed structure should be designed with flexible couplings, so minor deviations in alignment do not result in breakage or distress. Utility knockouts in grade beams should be oversized to accommodate differential movements. Surface Drainage Positive drainage should be provided during construction and maintained throughout the life of the proposed residence. Infiltration of water into utility or foundation excavations must be prevented during construction. Planters and other surface features which could retain water in areas adjacent to the building or pavements should be sealed or eliminated. In areas where slabs do not immediately adjoin the structure, we recommend that protective slopes be provided with a minimum grade of approximately 10 percent for at least 10 feet from perimeter walls. Backfill against footings, exterior walls, and in utility and sprinkler line trenches should be well compacted and free of all construction debris to reduce the possibility of moisture infiltration. Downspouts, roof drains or scuppers should discharge into splash blocks or extensions when the ground surface beneath such features is not protected by exterior slabs or paving. Sprinkler systems should not be installed within 10 feet of foundation walls. Landscaped irrigation adjacent to the foundation system should be minimized or eliminated. • 11 Geotechnical Engineering Report Residence and Septic System 14259 Highway 392—Weld County, Colorado Terracon Project No. 21055043 Terracon GENERAL COMMENTS Terracon should be retained to review the final design plans and specifications so comments can be made regarding interpretation and implementation of our geotechnical recommendations in the design and specifications. Terracon also should be retained to provide testing and observation during excavation, grading, foundation and construction phases of the project. The analysis and recommendations presented in this report are based upon the data obtained from the borings performed at the indicated locations and from other information discussed in this report. This report does not reflect variations that may occur between borings, across the site, or due to the modifying effects of weather. The nature and extent of such variations may not become evident until during or after construction. If variations appear, we should be immediately notified so that further evaluation and supplemental recommendations can be provided. The scope of services for this project does not include either specifically or by implication any environmental or biological (e.g., mold, fungi, bacteria) assessment of the site or identification or prevention of pollutants, hazardous materials or conditions. If the owner is concerned about the • potential for such contamination or pollution, other studies should be undertaken. This report has been prepared for the exclusive use of our client for specific application to the project discussed and has been prepared in accordance with generally accepted geotechnical engineering practices. No warranties, either express or implied, are intended or made. Site safety, excavation support, and dewatering requirements are the responsibility of others. In the event that changes in the nature, design, or location of the project as outlined in this report are planned, the conclusions and recommendations contained in this report shall not be considered valid unless Terracon reviews the changes and either verifies or modifies the conclusions of this report in writing. • 12 • 9rorosed Res;dente 3-2 e P-I 117 E3-I S • 3 State F`c hway 392 LEGEND S TEST BOR:NGS FIGURE I: BORING LOCATION DIAGRAM ® PERCOLATION BORINGS FIGURE RESIDENCE & SEPTIC SYSTEM 0 TEMPORFR'Y BENCHMARK= BOTTOM BLACK 14259 HIGHWAY 392 FENCE INSULATOR AT OVERHEAD UTILTY POLE WELD COUNTY, COLORADO ASSUMED EL. = 1OO' Project Mngr. TGA Project No. 21055043 • Designed By: 1rerracon Scale: 1"= 100' Checked By. TGA Date: 7/20/05 1289 FIRST AVENUE Approved By: TGA GREELEY, COLORADO 80631 Drawn By. JSD DIAGRAM BASED ON INFORMATION GATHERED DURING SITE VISIT. IS NOT INTENDED FOR CONSTRUCTION PURPOSES. ,Fla Name: 21055043.dwg Figure No. 1 • • LOG OF BORING NO. B-1 Page 1 of 1 CLIENT • Mr. Matt Green SITE 14259 Highway 392 PROJECT Weld County, CO Proposed Residence and Septic System SAMPLES TESTS { C7 OJ o Do DESCRIPTION >2 z F >- Z ILO Cr) W > (I) CCw Z Zz a H cn 0° w 0 �z Ow w ai ) >. O o Qo C j Z Approx. Surface Elev.: 98.5 ft ❑ D Z CC CO 5o ❑ Q ❑rn —'' 0.5 TOPSOIL 98 SANDY LEAN CLAY, medium stiff to stiff, _ CL 1 SS 9 5.3 dark brown to light brown (CL) CL 2 RS 5 24.0 99 5 2 • _ CL 3 RS 7 26.7 101 10 (4484.5 CLAYEY SAND, loose, light brown (SC) SC 4 SS 9 19.1 7 15 83.5 15 END OF BORING •i -J J The stratification lines represent the approximate boundary lines between soil and rock types: in-situ,the transition may be gradual. WATER LEVEL OBSERVATIONS, ft BORING STARTED 7-11-05 WL 6.5 WD 5.5 AB BORING COMPLETED 7-11-05 WL lerracon RIG CME-75 FOREMAN JSD WL AB checked after 24 hours. JOB# 21055043 • • LOG OF BORING NO. B-2 Page 1 of 1 CLIENT Mr. Matt Green SITE 14259 Highway 392 PROJECT Weld County,CO Proposed Residence and Septic System SAMPLES TESTS o p o n o DESCRIPTION > Z z_ w w c9 z> �w z Z Q a o 2 a oo al O Qz >- OcCC t • Approx. Surface Elev.: 99.5 ft o z CC CO 5 o o a u~i 0.5 TOPSOIL __ gg SANDY LEAN CLAY, medium stiff to stiff, _ CL 1 SS 5 6.6 dark brown to brown (CL) CL 2 RS 5 24.1 100 5• / With clayey sand lenses at 8 to 10 feet. — CL 3 SS 9 20.9 10 - _ CL 4 SS 9 19.5 15 84.5 15 END OF BORING C C.) Z Y u 0 The stratification lines represent the approximate boundary lines 7r between soil and rock types: in-situ, the transition may be gradual. N WATER LEVEL OBSERVATIONS, ft BORING STARTED 7-11-05 WL 5.0 WD L 5.0 AB BORING COMPLETED 7-11-05 _WL y lerracon RIG CME-75 FOREMAN JSD 0 WL AB checked after 24 hours. JOB# 21055043 LOG OF BORING NO. P-1 Page 1 of 1 CLIENT • Mr. Matt Green SITE 14259 Highway 392 PROJECT Weld County, CO Proposed Residence and Septic System SAMPLES TESTS o O E DESCRIPTION c 2 W z Z = I N w > CO Z W Z Z Z CL ¢ a U CO 0- 0 0 Hz > 0K o Approx. Surface Elev.: 99.5 ft o CO Z )- CC m 3 0 Ca D m 0.5 TOPSOIL 99 SANDY LEAN CLAY, medium stiff, brown _ to light brown/tan (CL) 5 CL 1 SS 5 28.2 148 91.5 • END OF BORING ;v The stratification lines represent the approximate boundary lines between soil and rock types: in-situ, the transition may be gradual. WATER LEVEL OBSERVATIONS, ft BORING STARTED 7-11-05 WL s 7.0 WD 1 6.0 AB BORING COMPLETED 7-11-05 WL Y lierracon RIG CME-75 FOREMAN JSD WL AB checked after 24 hours. JOB# 21055043 • • -4- _-____ - -�-- - 2 I --- 642 2 • 6 r i 8. 10 -I i . 0.1 1 10 PRESSURE,KSF Specimen Identification Classification Yd, pcf WC,% • B-1 4-eft SANDY LEAN CLAY(CL) 99 24 z Notes: Water added at 0.5 ksf. w • ±— ---- - --'- Q CONSOLIDATION TEST 7,3 Project: Proposed Residence and Septic System iierracon Site: 14259 Highway 392 Weld County, CO o Job#: 21055043 Date: 7-20-05 • • GENERAL NOTES DRILLING&SAMPLING SYMBOLS: • SS: Split Spoon- 1-3/8"I.D.,2"O.D.,unless otherwise noted HS: Hollow Stem Auger ST: Thin-Walled Tube-2"O.D.,unless otherwise noted PA: Power Auger RS: Ring Sampler-2.42"I.D., 3"O.D.,unless otherwise noted HA: Hand Auger DB: Diamond Bit Coring-4", N, B RB: Rock Bit BS: Bulk Sample or Auger Sample WB: Wash Boring or Mud Rotary The number of blows required to advance a standard 2-inch O.D. split-spoon sampler (SS) the last 12 inches of the total 18-inch penetration with a 140-pound hammer falling 30 inches is considered the"Standard Penetration"or"N-value". WATER LEVEL MEASUREMENT SYMBOLS: WL: Water Level WS: While Sampling WCI: Wet Cave in WD: While Drilling DCI: Dry Cave in BCR: Before Casing Removal AB: After Boring ACR: After Casing Removal Water levels indicated on the boring logs are the levels measured in the borings at the times indicated. Groundwater levels at other times and other locations across the site could vary. In pervious soils, the indicated levels may reflect the location of groundwater. In low permeability soils,the accurate determination of groundwater levels may not be possible with only short-term observations. DESCRIPTIVE SOIL CLASSIFICATION: Soil classification is based on the Unified Classification System. Coarse Grained Soils have more than 50% of their dry weight retained on a #200 sieve; their principal descriptors are: boulders, cobbles, gravel or sand. Fine Grained Soils have less than 50% of their dry weight retained on a #200 sieve; they are principally described as clays if they are plastic,and silts if they are slightly plastic or non-plastic. Major constituents may be added as modifiers and minor constituents may be added according to the relative proportions based on grain size. In addition to gradation, coarse-grained soils are defined on the basis of their in-place relative density and fine-grained soils on the basis of their consistency. • CONSISTENCY OF FINE-GRAINED SOILS RELATIVE DENSITY OF COARSE-GRAINED SOILS Standard Unconfined Penetration or Standard Penetration Compressive N-value(SS) or N-value(SS) Strength,Qu,psf Blows/Ft. Consistency Blows/Ft. Relative Density <500 <2 Very Soft 0-3 Very Loose 500 - 1,000 2-3 Soft 4-9 Loose 1,001 - 2,000 4-6 Medium Stiff 10 -29 Medium Dense 2,001 - 4,000 7-12 Stiff 30-49 Dense 4,001 -- 8,000 13-26 Very Stiff 50+ Very Dense 8,000+ 26+ Hard RELATIVE PROPORTIONS OF SAND AND GRAVEL GRAIN SIZE TERMINOLOGY Descriptive Term(s)of other Percent of Major Component constituents Dry Weight of Sample Particle Size Trace < 15 Boulders Over 12 in. (300mm) With 15-29 Cobbles 12 in.to 3 in.(300mm to 75 mm) Modifier >30 Gravel 3 in. to#4 sieve(75mm to 4.75 mm) Sand #4 to#200 sieve(4.75mm to 0.075mm) RELATIVE PROPORTIONS OF FINES Silt or Clay Passing#200 Sieve(0.075mm) Descriptive Term(s) of other Percent of PLASTICITY DESCRIPTION constituents Dry Weight Term Plasticity Index Trace <5 Non-plastic 0 With 5- 12 Low 1-10 • Modifiers > 12 Medium 11-30 High 30+ lierracon Form 108-9-00 • • UNIFIED SOIL CLASSIFICATION SYSTEM Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests' Soil Classification IIII Group Symbol Group Name' Coarse Grained Soils Gravels Clean Gravels Cu 7 4 and 1 s Cc s 3° GW Well-graded gravel` More than 50%retained More than 50%of coarse Less than 5%fines` Cu<4 and/or 1 >Cc>3' GP Poorly graded gravel` fraction retained on on No.200 sieve No.4 sieve Gravels with Fines Fines classify as ML or MH GM Silty gravel°•°" More than 12%fines' Fines classify as CL or CH GC Clayey graver G. Sands Clean Sands Cu z 6 and 1s Cc s 3E SW Well-graded sand' 50%or more of coarse Less than 5%fines° Cu<6 and/or 1 >Cc>3E SP Poorly graded sand' fraction passes No.4 sieve Sands with Fines Fines classify as ML or MH SM Silty sand"' More than 12%fines° Fines Classify as CL or CH SC Clayey sand"' Fine-Grained Soils Silts and Clays inorganic PI>7 and plots on or above"A"line' CL Lean clay""' 50%or more passes the Liquid limit less than 50 Pi<4 or plots below"A'line' ML Sr"' No.200 sieve organic Liquid limit-oven dried <0.75 OL Organic clay""'"' Liquid limit-not dried Organic silt""1O Silts and Clays inorganic PI plots on or above"A"line CH Fat dayy' Liquid limit 50 or more PI lots below"A"line MH Elastic Silt",,organic Liquid limit-oven dried Organic clay""" <0.75 OH Liquid limit-not dried Organic sift."'" Highly organic soils Primarily organic matter,dark in color,and organic odor PT Peat "Based on the material passing the 3-in. (75-mm)sieve "If fines are organic, add"with organic fines"to group name. elf field sample contained cobbles or boulders, or both, add"with cobbles ' If soil contains≥ 15%gravel, add"with gravel'to group name. or boulders,or both'to group name.• J If Atterberg limits plot in shaded area,soil is a CL-ML,silty clay. cGravels with 5 to 12%fines require dual symbols. GW GM well graded '<If soil contains 15 to 29%plus No.200,add'with sand"or'with gravel with silt, GW-GC well-graded gravel with clay,GP-GM poorly gravel,"whichever Is predominant. graded gravel with silt,GP-GC poorly graded gravel with day. I-If soil contains z 30%plus No.200 predominantly sand,add °Sands with 5 to 12%fines require dual symbols: SW-SM well-graded "sandy to group name. sand with silt,SW-SC well-graded sand with day, SP-SM poorly graded M If soil contains≥30%plus No.200,predominantly gravel, sand with silt,SP-SC poorly graded sand with clay add"gravelly to group name. e �Dw.� "PI≥4 and plots on or above"A"line. Cu=Deo/Dro Cc= Die x Deo ° PI <4 or plots below"A"line. F If soil contains≥ 15%sand,add"with sand"to group name. PR plots on or above"A"line. °If fines classify as CL-ML, use dual symbol GC-GM,or SC-SM. o PI plots below'A"line. 60 7 ..1.. ---.- _ ... .,...'1-----I- t- .__.. For classification of fine-grained soils and fine-grained fraction ,, 50 _of coarse-grained soils -----t— •ce—._._ __--I V� Equation of"A"-line .J, +P Q Horizontal at P1=4 to LL=25.5. X 40 then P1=0.73(LL-20) O .. • Li.' �jl p Equation of'U'-line I G� z Vertical at 11=16 to PI=7, } 30 — then 131.0.9(LL-8) • --I_,-- — f 1 I ot rG r _..-.11 _....-.-.._.-.. MH or OH o_ -" --- '- t7 - ML or OL --I_..._-_ i I 4I 0 i- - _ .._ .. ..._.. ID0 10 16 20 30 40 50 60 70 80 90 100 110 LIQUID LIMIT(LL) lierracon Form 111-6/98 Hello