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Subsoils Study for Foundation Design
rM%1&%i^C&WA*A&AW W qW %R 41011 W I %A Geotechnical Engineering Report A Co _ my Road 320 Garfield C ant, Colorado Proposed Modular Home November 21, 2025 Prepared For: Sunlight Valley Holdings LLC Attn: Terry Hale 251 Little Falls Drive Wilmington, Delaware 19808 GeoStrata Job No. 1869-004 Office — 2487 Industrial Boulevard #1, Grand Junction, Colorado 81505 Phone (801) 501-0583 1 info@geostrata-Ilc.com TABLE OF CONTENTS 1.0 EXECUTIVE SUMMARY...................................................................................1 2.0 INTRODUCTION..................................................................................................3 2.1 PURPOSE AND SCOPE OF WORK......................---.....................................3 2.2 PROJECT LOCATION AND EXISTING CONDITONS.............................3 3.0 METHODS OF STUDY........................................................................................5 3.1 FIELD INVESTIGATION................................................................................5 3.2 LABORATORY TESTING..............................................................................6 4.0 GENERALIZED SITE CONDITIONS...............................................................7 4.1 SURFACE CONDITIONS..............................................................................-1 4.2 GENERAL SUBSURFACE CONDITIONS...................................................7 4.2.1 Soils..................................................................................................................7 4.2.2 Groundwater....................................................................................................8 5.0 GEOLOGIC CONDITIONS................................................................................9 5.1 GEOLOGIC SETTING....................................................................................9 5.2 SEISMICITY AND FAULTING......................................................................9 6.0 ENGINEERING ANALYSIS AND RECOMMENDATIONS ........................11 6.1 GENERAL CONCLUSIONS.........................................................................11 6.2 EARTHWORK................................................................................................11 6.2.1 General Site Preparation and Grading.........................................................11 6.2.2 Excavation Stability.......................................................................................12 6.2.3 Structural Fill and Compaction.....................................................................12 6.3 FOUNDATIONS..............................................................................................14 6.3.1 Installation and Bearing Material.................................................................14 6.3.2 Bearing Pressure...........................................................................................14 6.3.3 Settlement.......................................................................................................14 6.3.4 Construction Observation..............................................................................15 6.4 CONCRETE SLAB -ON -GRADE CONSTRUCTION.................................15 6.5 EARTH PRESSURES AND LATERAL RESISTANCE .............................1 S 6.6 MOISTURE PROTECTION AND SURFACE DRAINAGE .....................17 6.7 SOIL CORROSIVITY .... . .................. ................. — .......................... 18 Copyright 0 2025 GeoStrata i Project 1869-004 7.0 CLOSURE............................................................................................................20 7.1 LIMITATIONS..................................................................... ..........................20 7.2 ADDITIONAL SERVICES ................................................... ...— ................... 20 8.0 REFERENCES CITED.......................................................................................22 APPENDICES Appendix A Plate A-1 ................................Site Vicinity Map Plate A-2 ................................Exploration Location Map Appendix B Plates 13-1 and B-2 .................Test Pit Logs Plate B-3.................................Key to Soil Symbols and Terms Appendix C Plate C-1.................................Lab Summary Table Plate C-2.................................Atterberg Limits Test Results Plate C-3.................................Grain Size Distribution Test Results Plates C-4 and C5................... 1-D Consolidation/Swell Test Results Appendix D Plate D-1 to D-6.....................Project Site Photographs Appendix E Plate E-1 and E-2 .Important Information about this Report Copyright 0 2025 GeoStrata ii Project 1869-004 1.0 EXECUTIVE SUMMARY This report presents the results of our geotechnical investigation and laboratory data collection conducted for the proposed new residence at 5810 County Road 320 in Garfield County, Colorado. We understand the proposed construction to include the removal of the existing modular home and construction of a new modular home to the south. The proposed square footage, loadings, and possible below grade areas (such as a crawl space or basement) were unknown to us at the time of this report. We understand that the proposed construction of the new residence will likely consist of a prefabricated modular home with a wood frame and masonry veneer exterior bearing on native soils or properly placed and compacted structural fill material consisting of imported or reprocessed existing native soils with cuts/fills of less than 4 feet. Based on the subsurface conditions encountered at the site, it is our opinion that the subject site is suitable for the proposed construction provided that the recommendations contained in this report are complied with. The recommendations herein should be considered preliminary until actual construction (structure) loadings are made known to us. The subsurface soils conditions were explored at the subject property by advancing two test pits to depths ranging from 5 to 10 feet below existing surface grades. The two test pit locations for the proposed modular home were located on the property with the assistance of the Owner's on - site representative. Groundwater was not encountered to the depths explored at the time of test pit excavation as part of this geotechnical investigation. However, seasonal fluctuations in precipitation, surface runoff, or other on or offsite sources may also increase moisture and groundwater conditions. Laboratory data, geotechnical evaluation and observations, and construction recommendations are provided regarding proposed construction. Key points discussed herein are the following: • Proposed square footage, loadings, and possible below grade areas (such as a crawl space or basement) were unknown to us at the time of this report. ■ A bearing pressure of 2,000 pounds per square foot can be used for foundation design, alternates are provided later in this report. • Soft, loose, and disturbed material should be removed below foundation and slab on grade areas. • If encountered, undocumented fill should be removed a minimum of two feet below proposed footing elevation. Removed fill material may be replaced if properly processed and compacted as discussed below. • Subgrade native soil appears to be under -consolidated with low to moderate collapse potential and strength. In our opinion subgrade soils can be suitable for use in proposed construction if properly processed and compacted to at least 95% of the maximum dry density as determined by ASTM D-698 (standard Proctor) or ASTM D-1557 (modified Proctor) depending on material classification, near OMC. • Recommendations herein shall be followed for construction. Copyright © 2025 GeoStrata 1 R1869-004 NOTICE: The scope of services provided within this report is limited to the assessment of the existing subsurface conditions at the time of our investigation for the proposed modular home construction as explained to us by the Client. In the event that existing conditions change, results and recommendations contained in this report may need to be modified. This executive summary is not intended to replace the report of which it is part and should not be used separately from the report. The executive summary is provided solely for purposes of overview. The executive summary omits a number of details, any one of which could be crucial to the proper application of this report. A two -page document prepared by GBA explains these items with greater detail which is found in Appendix E (Plates E-1 and E-2). Copyright © 2025 GeoStrata 2 R1869-004 2.0 INTRODUCTION 2.1 PURPOSE AND SCOPE OF WORK This report presents the results of a geotechnical investigation completed for the proposed modular home located at 5810 County Road 320 in Garfield County, Colorado (see Plates A-1, Site Vicinity Map and A-2 Site Exploration Map in Appendix A). Based on information provided by the Client, we understand the proposed construction at the site is to demolish and remove the existing modular home and construct the new modular home south of the existing modular home as shown on Plate A-2, Exploration Location Map. At the time of this report, it was unknown if below grade areas were planned. This investigation was completed through the advancement of two exploratory test pits in the approximate vicinity of the proposed construction per the Owner's on -site representative. The purposes of this investigation were to perform a field investigation to gather pertinent information regarding the subsurface conditions at the subject site and collect samples for laboratory testing in order to provide data, develop opinions and provide recommendations to Sunlight Valley Holdings LLC, for construction of the proposed new modular home. We understand that the proposed construction will likely consist of a prefabricated modular home with a wood frame and masonry veneer exterior bearing on native soils or on properly placed and compacted fill material with cuts/filly of less than 4 feet. Proposed structure loadings were not provided at the time of this report. Evaluations for additional scope items may be performed at a future date for an additional fee, if requested. The scope of work completed for this study included site reconnaissance, subsurface exploration including two test pits at the area of proposed construction, sample collection and laboratory testing, engineering analyses, recommendations for use in slabs on grade and foundation elements, and preparation of this report. Our services were performed in accordance with our proposal dated October 21, 2025, and your signed authorization also dated October 21, 2025. The recommendations contained in this report are subject to the limitations presented in Limitations (Section 7.1) of this report. 2.2 PROJECT LOCATION AND EXISTING CONDITONS The project site at 5810 County Road 320 is located approximately 500 feet south of County Road 320 in Garfield County, Colorado. The site is occupied by an existing modular home that is to be removed with an above ground propane tank on the east side of the property and an underground septic system to the west side of the existing residence. Existing power enters the Copyright 0 2025 GeoStrata 3 R1869-004 existing residence from overhead lines from the northeast. The site topography slopes gently downhill from the east to the west at an approximate 40H:1 V grade. Approximately 150 feet south of the proposed site is an approximately 155-foot-tall hill that steeply slopes downhill from the south to the north on its north side towards the proposed modular home at an approximate slope of 3H:1V (photograph in Appendix D, Plate D-2). The site is bound to the on all sides by irrigated pastures and farmland with sparce associated residences and structures and relatively undeveloped land consisting of native grasses. The Colorado River is approximately 0.6 miles west of the site. Scattered oil and gas well pads are throughout the general area and as close as approximately 200 feet east of the site. Project site photos are found in Appendix D, Plates D-1 through D-6. Specific project site conditions are discussed below in Surface Conditions (Section 4.1) of this report. Copyright © 2025 GeoStrata 4 R1869-004 3.0 METHODS OF STUDY 3.1 FIELD INVESTIGATION As a part of this investigation, subsurface soil conditions were explored at the project site by advancing two test pits to depths of 5 to 10 feet below existing grades. It should be noted that the locations of the test pits were determined by excavation equipment accessibility and information provided by the Owner's on -site representative. The approximate locations of the explorations are shown on Plate A-2, Exploration Location Map, in Appendix A. Our exploration locations were measured from existing landmarks and reported as latitude, longitude and elevations obtained from Google Earth on the Test Pit Logs shown in Appendix B. In our opinion, the selected locations provide a reasonable estimate of the subsurface soil conditions within the areas of the proposed construction. We recommend a site visit be performed by GeoStrata when excavations are complete, and prior to footing construction, to assess subgrade conditions throughout the excavation areas. Subsurface soil conditions encountered in the explorations were logged at the time of our investigation by a qualified geotechnical engineer and are presented on the enclosed exploration Test Pit Logs, Plates B-1 and B-2 in Appendix B. Test Pit Excavation was completed on October 28, 2025. Prior to our field exploration, ,test pits were marked with lathe and white paint, and utility locates were performed by calling UNCC and meeting at the project site. After excavation, the test pits were backfilled with the excavated soils. Backfilling of the test pits was not observed. It should be noted that we attempted to locate our test pits outside of the proposed modular home footprint so that construction would not occur on top of the potentially uncompacted backfill of the test pits. Test pits were excavated using a Caterpillar 305 mini-trackhoe to pre -determined depths for sampling and to evaluate the subsurface. Bedrock was not encountered in test pit locations and estimations of bedrock depth was outside the scope of service. At selected intervals, a 2-inch interior diameter (ID) thin -walled liner was driven by hand into subsurface materials to obtain samples. Samples obtained during the field explorations were examined by GeoStrata staff and representative samples were submitted for laboratory testing to evaluate the engineering characteristics of the materials encountered. Copyright 0 2025 GeoStrata 5 R1869-004 Bulk samples were collected from the test pit spoils as representative of subsurface soils not obtained in the liner samples. All samples were transported to our laboratory for further testing to evaluate engineering properties of the various earth materials observed. Subsurface soil conditions as encountered in the test pit explorations logged at the time of our investigation by GeoStrata staff are presented on the enclosed Test Pit Logs, Plates B-1 and B2 in Appendix B. A Key to Soil Symbols and Terminology is presented on Plate B-3. Samples obtained during the field explorations were examined by GeoStrata staff and representative samples were submitted for laboratory testing to evaluate the engineering characteristics of the materials encountered. The soils were classified according to the Unified Soil Classification System (USCS) by the Geotechnical Engineer. 3.2 LABORATORY TESTING Geotechnical laboratory tests were conducted on samples obtained during our field investigation. The laboratory testing program was designed to evaluate the engineering characteristics of onsite earth materials. Laboratory tests conducted during this investigation include: - Grain Size Distribution Analysis (ASTM D422) - Atterberg Limits (ASTM D4318) - 1-D Consolidation / Swell Test (ASTM D2435) - Water Soluble Sulfate Content (ASTM C1580) - Water Soluble Chloride Content (ASTM T291) - Soil Electrical Resistivity and pH to evaluate corrosion potential of ferrous metals in contact with site soils The results of laboratory tests are presented on the Test Pit Logs in Appendix B (Plates B-1 and B-2), the Laboratory Summary Table, and the test result plates presented in Appendix C (Plates C-1 to C-5). Copyright © 2025 GeoStrata 6 R1869-004 4.0 GENERALIZED SITE CONDITIONS 4.1 SURFACE CONDITIONS At the time of our project field investigation, the subject site was occupied by an existing modular home that is to be removed with an above ground propane tank on the east side of the property and an underground septic system to the west side of the existing residence. Existing power enters the existing residence from overhead lines from the northeast. The site topography slopes gently downhill from the east to the west at an approximate 40H:1 V grade. Approximately 150 feet south of the proposed site is an approximately 155-foot-tall bluff that steeply slopes downhill from the south to the north at an approximate slope of 3H:IV. The site is bound on all sides by irrigated pastures and farmland with sparce associated residences and structures and relatively undeveloped land consisting of native grasses. The Colorado River is approximately 0.6 miles west of the site. Scattered oil and gas well pads are throughout the general area and as close as approximately 200 feet east of the site. Elevation of the existing ground surface at the location of the proposed modular home is estimated at between 5,305 to 5,315 feet above MSL based on Google Earth. 4.2 GENERAL SUBSURFACE CONDITIONS As previously discussed, the subsurface soil conditions were explored at the site by advancing two test pits in the general location of the proposed modular home to depths of approximately 5 and 10 feet. The soils encountered were visually classified and logged during our field investigation and are included on the Test Pit Logs (Plates B-1 and B-2). A Key to Soil Symbols and Terminology is presented on Plate B-3. Additional discussions concerning the soil encountered in our investigations are provided below. 4.2.1 Soils Based on our observations and geologic literature review, the subject site is overlain by approximately 0 to 10 feet of fine-grained sediments consisting of Lean CLAY (CL) which contain occasional granular seams consisting of Poorly Graded GRAVEL (GP) with sand. It is considered likely that these sediments represent possible alluvial (Qf) or eolian (Qlo) deposits as mapped by Shroba and Scott (1997). Copyright © 2025 GeoStrata 7 R1869-004 GRAVEL - One sample of the Sandy Gravel lenses had 3% fines (material passing the No. 200 sieve). Atterberg limits testing had a liquid limit and plasticity index of 0 (non -plastic). CLAY - Two samples of the Sandy to Very Sandy, Slightly Gravelly, Lean Clay tested (with Gravel lenses) had 55 and 71 % percent fines (material passing the No. 200 sieve). One sample tested for Atterberg limits had a liquid limit of 26 and a plasticity index of 8. Two samples tested exhibited collapse potential of 0.2 and 3.6 percent when wetted under an applied pressure of 1,000 psf. An unconfined compressive test was completed on a sample of the subsurface fine-grained sediments obtained from Test Pit 2 at a depth of 3 feet; however, the sample disaggregated prior to the completion of the test. 4.2.2 Groundwater Groundwater was not encountered at the time of drilling. Seasonal fluctuations in precipitation, surface runoff from adjacent properties, or other sources on or offsite may also increase moisture and groundwater conditions; however, it is not anticipated that groundwater will impact the proposed construction. Based on observed subsurface conditions, perched groundwater may be encountered during spring snowmelt due to low permeable clay and sandy clay and should be anticipated depending on season of construction. Copyright 0 2025 GeoStrata 8 R1869-004 5.0 GEOLOGIC CONDITIONS 5.1 GEOLOGIC SETTING The site is located within the eastern portion of the Piceance Basin, a relatively large geological structural basin formed during the Laramide Orogeny in northwestern Colorado. The basin is bound by the Cathedral Bluffs to the west and by the Grand Hogback to the east. Both the Cathedral Bluffs and the Grand Hogback are upward -bending formations rising to the surface, resulting in a "sag" between them. The Piceance Basin is permeated by a large number of folds and faults, and is relatively deep, with the area initially receiving significant amounts of cretaceous -aged sediments and then hosting a series of large freshwater lakes throughout the last 40 million years (Shroba, Green, and Fairer, 1995). These lakes resulted in relatively thick sequences of lacustrine sediments that have given rise to significant oil and natural gas deposits. The Colorado River has since eroded into the relatively soft tertiary and cretaceous sediments, with the elevation of the Colorado River relative to the existing basin elevation has caused the impedance of the flow of the Colorado River, resulting in a low stream gradient and causing the river to meander into the softer cretaceous rocks resulting in the widening evolution of the Rifle Valley. Near surface sediments at the site are mapped on the 1:24,000 scale Geologic Map (Shroba and Scott, 1997) as consisting of Pleistocene -aged loess deposits (Qlo) consisting of clay, silt and sand. Bedrock deposits mapped as being exposed on adjacent properties are mapped as consisting of the Shire Member of the Wasatch Formation (Tws). The Wasatch Formation is described as being deposited in alluvial, fluvial, and lacustrine environments and consists of sandstone, siltstones, mudstones and shales with occasional coal seams throughout. 5.2 SEISMICITY AND FAULTING The nearest fault to the subject site is the Gore Range frontal fault, which is mapped approximately 80 miles east of the subject site. The Gore Range frontal fault bounds the eastern margin of the Gore Range and is also known as the Blue River fault and the Frontal fault. The Gore Range frontal fault is a high -angle, left -stepping, down to the northeast fault, and has produced a major bedrock scarp up to 610 meters high near Boulder Creek. While work continues on dating the most recent rupture along this fault, it is thought to have last moved during the latest Quaternary (less than 15,000 years ago). Copyright © 2025 GeoStrata 9 RI869-004 The site is also located approximately 801h miles to the west of the Mosquito fault, a range -front fault on the west flank of the Tenmile and Mosquito Ranges and may represent a southern extension of the Gore Fault described previously. The fault is a high -angle normal fault that is down to the west and northwest and has observed offset in late Quaternary glacial deposits. Spectral responses for the Risk -Targeted Maximum Considered Earthquake (MCER) are shown in the table below. These values generally correspond to a one percent probability of structure collapse in 50 years for a "firm rock" site. To account for site effects, site coefficients which vary with the magnitude of spectral acceleration are used. Based on our field exploration and the estimated soil conditions from the areas geologic surficial deposits as indicated by Shroba and Scott (1997), it is our opinion that this location is best described as a Site Class D (Stiff Soil). The spectral accelerations are calculated based on the site's approximate latitude and longitude of 39.4497260' and-107.860446' respectively and the Seismic Design Maps web -based application at h9Rs://seismicmgps.orP_/- Description Site Class Value D SS - MCER ground motion (period — 0.2s) 0.319 Sl - MCER ground motion (period —1.0s) 0.075 Fa - Site amplification factor at 1.0s 1.545 F, - Site amplification factor at 1.Os 2.400 PGA - MCER peak ground acceleration 0.191 PGAm —Site modified peak ground acceleration 0.270 It should be noted that our investigation did not include a site -specific ground motion hazard analysis, and a Site Class D (Stiff Soil) has been used to determine the seismic parameters presented above based on known geologic conditions of the surficial deposits at the site and according to the Section 20.1 of ASCE 7. The seismic parameters presented herein may be used for design of the proposed structures provided that structural design allows for the ground motion hazard analysis exception in ASCE 7-16 Segment 11.4.8. The seismic data provided above should be used by the project geotechnical and structural engineers for proper site and structural design. GeoStrata recommends that a licensed structural engineer provide proper structural designs for all proposed structures which account for and mitigate this hazard. It is the opinion of GeoStrata that earthquake ground shaking hazard should not preclude development. Copyright © 2025 G6oStrata 10 R1869-004 6.0 ENGINEERING ANALYSIS AND RECOMMENDATIONS 6.1 GENERAL CONCLUSIONS Supporting data upon which the following recommendations are based have been presented in the previous sections of this report. The recommendations presented herein are governed by the physical properties of the earth materials encountered and tested as part of our subsurface exploration and the anticipated design data discussed in the Introduction (Section 2.0) of this report. If subsurface conditions other than those described herein are encountered in conjunction with construction, and/or if design and layout changes are initiated, GeoStrata must be informed so that our recommendations can be reviewed and revised as changes or conditions may require. Based on the subsurface conditions encountered at the site, it is our opinion that the subject site is suitable for the proposed development provided that the recommendations contained in this report are incorporated into the design and construction of the project. 6.2 EARTHWORK Prior to the placement of foundations, general site grading is recommended to provide proper support for foundations, exterior concrete flatwork, and concrete slabs -on -grade. Site grading is also recommended to provide proper drainage and moisture control on the subject property and to aid in preventing differential settlement of foundations as a result of variations in subgrade moisture conditions. 6.2.1 General Site Preparation and Grading Within areas to be graded (below proposed structures, fill sections, concrete flatwork, or pavement sections), any existing vegetation, topsoil, undocumented fill, debris, or otherwise unsuitable soils should be removed. Any soft, loose, or disturbed soil should also be removed. Following the removal of vegetation, unsuitable soils, and loose or disturbed soils, as described above, site grading may be conducted to bring the site to design elevations. As over -excavation is required, the excavation should extend a minimum of one foot laterally for every foot of depth of over -excavation. Excavations should extend laterally at least two feet beyond flatwork, pavements, and slabs -on -grade. Copyright © 2025 GeoStrata 11 R1869-004 A GeoStrata representative should observe the site preparation and grading operations to assess that the recommendations presented in this report are complied with. 6.2.2 Excavation Stability Based on Occupational Safety and Health Administration (OSHA) guidelines for excavation safety, trenches with vertical walls up to 5 feet in depth may be occupied, however, the presence of fill soils, loose soils, or wet soils may require that the walls be flattened to maintain safe working conditions. When the trench is deeper than 5 feet, we recommend a trench -shield or shoring be used as a protective system to workers in the trench. Based on our soil observations, laboratory testing, and OSHA guidelines, native soils at the site should be classified as Type C soils due to the cobbles/boulders encountered in the vicinity of the area based on this and additional studies performed. Deeper excavations, if required, should be constructed with side slopes no steeper than one and one-half horizontal to one vertical (1.5H:1V). If wet conditions are encountered, side slopes should be further flattened to maintain slope stability. Alternatively, shoring or trench boxes may be used to improve safe work conditions in trenches. The contractor is ultimately responsible for trench and site safety. Pertinent OSHA requirements should be met to provide a safe work environment. If site specific conditions arise that require engineering analysis in accordance with OSHA regulations, GeoStrata can respond and provide recommendations as needed. We recommend that a GeoStrata representative be on -site during all excavations to assess the exposed foundation soils. We also recommend that the Geotechnical Engineer be allowed to review the grading plans when they are prepared in order to evaluate their compatibility with these recommendations. 6.2.3 Structural Fill and Compaction All fill placed for the support of structures, concrete flatwork or pavements should consist of structural fill. Structural fill may consist of reworked native fine-grained or coarse -grained soil. Where these soils are to be used as structural fill, all organic debris as well as gravels and cobbles larger than 4 inches in nominal diameter should be screened from material being used as structural fill. Care will need to be taken to ensure that the fine-grained material is thoroughly processed and no "clods" that preserve a collapse potential are incorporated into the fill section. Alternatively, an imported fill meeting the specifications of the Colorado Department of Transportation Class 2 Aggregate Base Course may be used. Regardless of if the structural fill is Copyright 0 2025 GeoStrata 12 R1869-004 imported or native, it should be free of vegetation (less than 3 percent organic content), debris or frozen material, and should contain no inert materials larger than 4 inches nominal size. It should be noted that rounded gravel and rock can be difficult to compact and should be crushed at the plant prior to being brought on site. Soils not meeting the aforementioned criteria may be suitable for use as structural fill. This soil should be evaluated on a case -by -case basis and should be approved by the Geotechnical Engineer prior to use. The contractor should anticipate testing all soils used as structural fill frequently to assess the maximum dry density, fines content, and moisture content, etc. All structural fill should be placed in maximum 6-inch loose lifts if compacted by small hand - operated compaction equipment, maximum 8-inch loose lifts if compacted by light -duty rollers, and maximum 12-inch loose lifts if compacted by heavy duty compaction equipment that is capable of efficiently compacting the entire thickness of the lift. We recommend that all structural fill be compacted on a horizontal plane, unless otherwise approved by the geotechnical engineer. Structural fill should be compacted to at least 95% of the maximum dry density, as determined by ASTM D-698 or ASTM D-1557, depending on soil classification. The moisture content should be at or slightly above the optimum moisture content at the time of placement and compaction. Also, prior to placing any fill, the excavations should be observed by the geotechnical engineer to observe that any unsuitable materials or loose soils have been removed. In addition, proper grading should precede placement of fill, as described in the General Site Preparation and Grading (Section 6.2.1) of this report. Fill soils placed for subgrade below exterior flat work, should be at or slightly above the optimum moisture content when placed and compacted to at least 95% of the maximum dry density as determined by ASTM D-698 or ASTM D-1557. All utility trenches backfilled below the proposed structure, pavements, and flatwork concrete, should be backfilled with structural fill that is within 3% of the OMC when placed and compacted to at least 95% of the maximum dry density as determined by ASTM D-698 or ASTM D-1557. All other trenches, in landscape areas, should be backfilled and compacted to at least 90% of the maximum dry density (ASTM D-698 or D-1557). The gradation, placement, moisture, and compaction recommendations contained in this section meet our minimum requirements but may not meet the requirements of other governing agencies such as city, county, or state entities. If their requirements exceed our recommendations, their specifications should override those presented in this report. Copyright 0 2025 GeoStrata 13 R1869-004 6.3 FOUNDATIONS The foundations for the proposed structures may consist of conventional strip and/or spread footings. Strip and spread footings should be a minimum of 16 and 24 inches wide, respectively, and shallow exterior footings should be embedded at least 36 inches for frost protection and confinement. Interior shallow footings should be embedded at least 18 inches for confinement. Results of two swell tests completed on representative samples of this soil indicated a -0.2 and -3.6 (collapse) percent volumetric change when wetted under an applied pressure of 1,000 psf. As such, it is our opinion that the soil at the site has a moderate potential for hydro -consolidation upon loading and wetting. 6.3.1 Installation and Bearing Material Considering the moderate potential for hydro -consolidation discussed above, it is our recommendation that foundation excavations extend a minimum depth of three feet below proposed bottom of footing elevation and grade be reestablished utilizing on site soils or imported material as structural fill, moisture conditioned and compacted as described above. Foundation elements should not be founded on undocumented fill soils, and if these soils are encountered, they should be over -excavated until suitable, native soils are exposed. Structural fill should meet material recommendations and be placed and compacted as recommended in Structural Fill and Compaction (Section 6.2.3). 6.3.2 Bearing Pressure Conventional strip and spread footings founded as described above may be proportioned for a maximum net allowable bearing capacity of 2,000 psf. The net allowable bearing capacity may be increased (typically by one-third) for temporary loading conditions such as transient wind and seismic loads. All footing excavations should be observed by the Geotechnical Engineer prior to placement of footing concrete. 6.3.3 Settlement Settlements of properly designed and constructed conventional footings, founded as described above, are anticipated to be less than I inch. Differential settlements should be on the order of half the total settlement over 30 feet. As water infiltration may induce settlement even under recommended conditions it is important to divert any surface water away from foundation elements as described in Moisture Protection and Surface Drainage (Section 6.6). Copyright 0 2025 GeoStrata 14 R1869-004 6.3.4 Construction Observation A geotechnical engineer shall periodically monitor excavations prior to installation of footings. Inspection of soil before placement of structural fill or concrete is required to detect any field conditions not encountered in the investigation which would alter the recommendations of this report. All structural fill material shall be tested under the direction of a geotechnical engineer for material and compaction requirements. 6.4 CONCRETE SLAB -ON -GRADE CONSTRUCTION Concrete slabs -on -grade should be constructed over at least 4 inches of compacted gravel overlying undisturbed native soils or structural fill. Structural fill should be compacted to at least 95% of the maximum dry density as determined by ASTM D-698 or ASTM D-1557 prior to placement of gravel. The gravel should consist of road base or clean drain rock with a 3/-inch maximum particle size and no more than 12 percent fines passing the No. 200 mesh sieve. The gravel layer should be compacted to at least 95 percent of the maximum dry density of modified proctor or until tight and relatively unyielding if the material is non-proctorable. All concrete slabs should be designed to minimize cracking as a result of shrinkage. Consideration should be . given to reinforcing the slab with welded wire, re -bar, or fiber mesh. A vapor barrier such as a Visqueen polyethylene (PE) vapor barrier or equivalent, may be considered as an alternative to the 4-inches of compacted gravel. The PE vapor barrier should be placed between the native soils or structural fill and the concrete for the floor slab. At the Owner's option, the requirement for 4-inches of gravel beneath interior slabs on grade, sidewalks, drives, or aprons may be omitted; however, if the 4-inches of gravel is omitted, settlement and cracking of these slabs may be more likely to occur. 6.5 EARTH PRESSURES AND LATERAL RESISTANCE Lateral forces imposed upon conventional foundations due to wind or seismic forces may be resisted by the development of passive earth pressures and friction between the base of the footing and the supporting subgrade. In determining the frictional resistance, a coefficient of friction of 0.43 should be used for native granular soils against concrete. A coefficient of friction of 0.34 should be used for native fine-grained soils against concrete. Copyright © 2025 GeoStrata 15 R1869-004 Ultimate lateral earth pressures from granular backfill acting against buried walls and structures may be computed from the lateral pressure coefficients or equivalent fluid densities presented in the following table: Lateral Pressure Equivalent Fluid Density CoefficientCondition .. per .. Active* 0.26 33 At -rest** 0.46 57 Passive* 8.08 1011 Seismic Active*** 0.13 17 Seismic Passive*** -1.22 -153 * Based on Coulomb's equation ** Based on Jaky *** Based on Mononobe-Okabe Equation Ultimate lateral earth pressures from fine grained backfill acting against buried walls and structures may be computed from the lateral pressure coefficients or equivalent fluid densities presented in the following table: Lateral Pressure Equivalent Fluid Density CoefficientCondition .. per .. Active* 0.32 40 At -rest** 0.53 66 Passive* 5.15 644 Seismic Active*** 0.15 19 Seismic Passive*** -0.84 -105 * Based on Coulomb's equation ** Based on Jaky *** Based on Mononobe-Okabe Equation These coefficients and densities assume level, granular backfill with no buildup of hydrostatic pressures. The force of the water should be added to the presented values if hydrostatic pressures are anticipated. If sloping backfill is present, we recommend the geotechnical engineer be consulted to provide more accurate lateral pressure parameters once the design geometry is established. Copyright 0 2025 GeoStrata 16 R1869-004 Walls and structures allowed to rotate slightly should use the active condition. If the element is constrained against rotation, the at -rest condition should be used. These values should be used with an appropriate factor of safety against overturning and sliding. A value of 1.5 is typically used. Additionally, if passive resistance is calculated in conjunction with frictional resistance, the passive resistance should be reduced by ''/z. For seismic analyses, the active and passive earth pressure coefficient provided in the table is based on the Mononobe-Okabe pseudo -static approach and only accounts for the dynamic horizontal thrust produced by ground motion. Hence, the resulting dynamic thrust pressure should be added to the static pressure to determine the total pressure on the wall. The pressure distribution of the dynamic horizontal thrust may be closely approximated as an inverted triangle with stress decreasing with depth and the resultant acting at a distance approximately 0.6 times the loaded height of the structure, measured upward from the bottom of the structure. The coefficients shown assume a vertical wall face. Hydrostatic and surcharge loadings, if any, should be added. Over -compaction behind walls should be avoided. Resisting passive earth pressure from soils subject to frost or heave, or otherwise above prescribed minimum depths of embedment, should usually be neglected in design. 6.6 MOISTURE PROTECTION AND SURFACE DRAINAGE Moisture should not be allowed to infiltrate the soils in the vicinity of the foundations. We recommend the following mitigation measures be implemented at the building location. Perched groundwater elevation can be altered by flood irrigation and/or other surges of water introduced to the subsurface. As an added precaution the following moisture protection mitigation recommendations should be implemented to help reduce the risk of potential settlement from occurring. These items are summarized as follows: • Moisture should not be allowed to infiltrate into the soils in the vicinity of the foundations. As such, design strategies to minimize ponding and infiltration near the home should be implemented. • The ground surface within 10 feet of the entire perimeter of the building should slope a minimum of 5% away from the structure. Alternatively, a slope of 2% is acceptable if the water is conveyed to a concrete ditch that will convey the water to a point of discharge that is at least 10 feet from the structures. Copyright 0 2025 GeoStrata 17 R1869-004 ■ Roof runoff devices (rain gutters) should be installed to direct all runoff a minimum of 15 feet away from the structure and preferably day -lighted to the curb where it can be transferred to the storm drain system. Rain gutters discharging roof runoff adjacent to or within the near vicinity of the structure may result in excessive differential settlement. ■ We do not recommend storm drain collection sumps be used as part of this development. However, if necessary, sumps should not be located within 20 feet of foundations elements. ■ We recommend irrigation around foundations be minimized by selective landscaping and that sprinklers be constructed at least 5 feet away from foundations. Sprinklers should be directed away from the foundation walls. We recommend that irrigation valves and supply lines be constructed at least 15 feet away from foundations. • Jetting (injecting water beneath the surface) to compact backfill against foundation soils may result in excessive settlement beneath the building and is not allowed. Backfill against foundations walls should be placed in lifts and compacted to 90% modified proctor to create a moisture barrier. In areas where collapsible soils are present, backfill should consist of fine-grained soils. Any additional precautions which may become evident during construction. Over -wetting of the native or fill soils beneath the footings by natural or man-made means prior to, during or after construction may result in soil stability problems and potential excessive settlement of the soils. Failure to comply with these recommendations could result in excessive total and differential settlements causing structural damage. 6.7 SOIL CORROSIVITY One soil sample was tested for soil chemical reactivity. Chemical reactivity tests were performed to determine soil pH, resistivity, and concentrations of water-soluble sulfate ions. Results from these tests are summarized in the table below; Test results indicate that the soluble sulfate concentrations of 49 ppm. Based on the American Concrete Institute (ACI) Building Code, these concentrations represent "negligible" degree of sulfate attack on concrete structures. Type I/II Portland Cement Concrete (PCC) may be used for Copyright 0 2025 GeoStrata 18 R1869-004 concrete elements in contact with the onsite soils or properly placed and compacted granular structural fill. Laboratory soil resistivity has a direct impact on the degree of corrosion in underground steel structures. A decrease in resistivity relates to an increase in corrosion activity and therefore dictates that protective treatment to be used. Results from the laboratory resistivity tests indicate a resistivity of 1,700 ohm -cm. Based on the resistivity test results, the onsite fine-grained soils are considered to be "highly corrosive" if saturated in the field. Results of the ion hydrogen concentration (pH) tests were 7.81. Concentrations above 7 are considered basic and are less likely to contribute to corrosion attack on subsurface steel structures. Anticipated underground steel structures (i.e., pipes, exposed steel) should be protected against corrosion. Copyright © 2025 GeoStrata 19 R1869-004 7.0 CLOSURE 7.1 LIMITATIONS The recommendations contained in this report are based on limited field exploration and our understanding of the proposed construction. This investigation was completed for the proposed construction and should not be used for other projects. The subsurface data used in the preparation of this report were obtained from the explorations made for this investigation. It is likely that variations in the soil and groundwater conditions will exist. The nature and extent of variations may not be evident until construction occurs. If any conditions are encountered at this site that are different from those described in this report, our firm should be immediately notified so that we may make any necessary revisions to the recommendations contained in this report. In addition, if the scope of the proposed construction changes from that described in this report, our firm should also be notified. This report was prepared in accordance with the generally accepted standard of practice at the time the report was written. No other warranty, expressed or implied, is made. It is the Client's responsibility to see that all parties to the project including the Designer, Contractor, Subcontractors, etc. are made aware of this report in its entirety. The use of information contained in this report for bidding purposes should be done at the Contractor's option and risk. 7.2 ADDITIONAL SERVICES The recommendations made in this report are based on the assumption that an adequate program of tests and observations will be made during the construction. GeoStrata staff should be on site to document compliance with these recommendations and to verify geologic conditions are as anticipated. Our services should include, but not necessarily be limited to, the following: • Observations and testing before and during site structural fill placement. • Consultation as may be required during construction, including verification that the geologic conditions are as anticipated during excavation and design of shoring if deemed necessary based on actual geologic conditions encountered during construction. • If GeoStrata is not involved in the construction process for observation and materials testing either the Contractor or the engineer consulted for observation and materials testing during construction assumes all liability. Copyright 0 2025 GeoStrata 20 R1869-004 We appreciate the opportunity to be of service on this project. Should you have any questions regarding the report or wish to discuss additional services, please do not hesitate to contact us at your convenience at (801) 501-0583. Copyright © 2025 GeoStrata 21 R1869-004 8.0 REFERENCES CITED Shroba, Ralph R., Scott, Robert B., 1997, Geologic Map of the Rifle Quadrangle, Garfield County, Colorado, U.S. Geological Survey,'Open-File Report 97-852. Shroba, Ralph R., Green, Morris W., Fairer, George M., 1995, Preliminary Geologic Map of the Rifle Quadrangle, Garfield County, Colorado, Open -File Report 95-52. Tweto, Ogden, 1979, Geologic Map of Colorado, United States Geological Survey, Map M(271) Copyright© 2025 GeoStrata 22 R1869-004 APPENDIX A 300 0 300 600 900 11200 ft N Legend'„. �w Approximate Site Boundary 1:5.000 / V Copyright, 2025 Sunlight Valley Holdings LLC 5810 CR 320 Modular Home Plate Garfield County, Colorado A-1 Project Number:1869-004 Site Vicinity Map J �;. yS 'x a. or :FA: � •r _ x .fir`;• � .� � ,r _ '� . 1 r' .fn.i1J_ = a dt 70 0 70 140 210 280 ft N Legend � � �4i E9 %Y�Yl g 1:1,500 Copyfiyht, 2025 Approximate Site Boundary Approximate Test Pit Locations Sunlight Valley Holdings LLC 5810 CR 320 Modular Home Plate Garfield County, Colorado Project Number:1869-004 A-2 Exploration Location Map APPENDIX B STARTED: 10/28/25 Sunlight Valley Holdings LLC GeuStrata Rep: R13 TEST PIT NO: 5810 CR 320 Modular CToine �_O Ll COMPLETED: 10/28/25 Geld County, Colorado Rig Type: Catepillar 305 BACKFILLED: 10/28/25 Protect Number 1869-004 Mini Ex Sheet 1 of 1 DEPTH LOCATION Moisture Content .a p O LATITUDE 39.4972 LONGITUDE-107.8605 ELEVATION 5,308-ft o c o and (y o ' Atterberg Limits .-.4�4 O o Y Plasmic Moisture Liquid a s U [6 V E Limit Content Limit MATERIAL DESCRIPTION uw ¢ w a 3 C7 c) G1 w a w 102030405060708090 0 0 '. TOPSOIL 5ann y €.can r st]ff io vary situ; moist, lighi brown CL - Poorly Graded GRAVEL with sand lensc only present at south wall of excavation about 1-foot thick 92.5 4.8 55.0 3.8 3.0 NP NP {..'... . ... 1 - Poorly Graded GRAVEL with sand lense only present at south wall 5 of excavation about 1-foot thick 2 3 10 {. Bottom of Test Pit @ 10 Feet 4- F-i F SAMPLE TYPE NOTES: w m - GRAB SAMPLE Elevations were estimated using Google Earth Plate O- 2 5" O D THIN -WALLED HAND SAMPLER Aoft C.6M&a6ow o '%Or 4W V ri 1 w %4 1 4' WATER LEVEL B— 1 N 1- MEASURED N Copyright (c) 2025, GeoSvata Q- ESTIMATED w STARTED: 10/28/25 Sunlight Valley Holdings LLC GeoStrataRep: RH TEST PIT NO Q 5810 CR 320 Modular Home �_02 Q COMPLETED: 10/28/25 Garfield County, Colorado Rig Type: Catepillar30S BACKFQ_T_FD: 10/28/25 Project Number 1869-004 Sheet I of I DEPTH .a O O LOCATION L.ATrrUDE 39.4971 LANGrruDE-107.8605 ELEVATION 5,308-ft a Moisture Content and Atterberg Limits > pU c r c Plastic Moisture Liquid W a U Q Limit Content Limit MATERIAL DESCRIPTION ~r~� 3 0U L a .a a 102030405060708090 0 TOPSOIL CL Lean CLAY with sand - srifl moist, light brown, scattered gravel 93.8 8.4 71.0 26 8 ; t 1 5 Bottom of Test Pit @ 5 Feet 2 3 10 4 SAMPLE TYPE NOTES: m - GRAB SAMPLE Elevations were estimated using Google Earth plate ♦` ��■ 2.5" O.D. THAT -WALLED HAND SAMPLER �► 4i i i# i %r& WATER LEVEL B _ 2 7- MEASURED Copyright (c) 2025, GeoS=La Q- ESTIMATED DESCRIPTION OF SYMBOLS Sample Type Water Level Disturbed or Bag Sample Y Water Level After a Specific Period of Time ❑ 3" OD "California" Style Split Barrel Sampler �2 Water Initially Encountered z2" OD Split Spoon Sampler Exploration Type ® Boring 3" OD Thin -Walled Shelby Tube Sampler FH Test Pit H 2.5" O.D./ 2" I.D. Sampler Location and Elevation Unless otherwise noted, Latitude and Longitude are approximately determined using a hand-held GPS device. The accuracy of such devices is variable. Surface elevation data annotated with +/- indicates that no actual topographical survey was conducted to confirm the surface elevation. Instead, the surface elevation was approximately determined from topographic maps of the area. Classification of Soils for(Unified Soil Classification S►rstetn aff!Ye:n 5AAL CLA_M:JMWAT10M SYSTEM IASTM 0 2JAU Terms Describing Consistence or Condition MOISTURE CONTENT CEMENTATION DE5CIR1PTh-A FIELD TE5r CrIrMes Or brisakS W ea ly vWth h&rl�ng or slight River pressure CruTibles a breaks Aloderalely YMh considerade Anger Will not +JlaMe or Slraigly nreakwitharve Pie Angularity Cu4 4 WELL �[K3EUGf7KyF15 M]fTLRES WITHWITM CLEAN C-RAYFISAND POORLY GRADED GMVELS FNES GISAVU MY7URES WI7lILITTLE ORNC3FMESW'�L{,RADEr;GRAVELSGfenvELs+woe+ucruRESWmILITTLE ro. Fs�S 1•CW�LGRN`GRAVELS GfUVF1SNJh!%fLRESWIrHWITHLIT TLE CLAY FY+FS5S r01T7i WORLY GRALL�.O GRAVELS.fI�S GRAVELSAVCM%TURESWrc!I uTTLEFNFSPOORLY GRAOEU tiRAVEI_S, GRAVEL RELA7IYE OENSrrY OF COAR9E-0AAII✓EDBQB COI619TENCY OF FBEiiRAWm8pl8 t50%mr mna gi3avy ela lJo 2roae�2 1 ILlera tlan 50`k relan®A on eb 2W vere.I COlsistenry deltlrrl'eled W �arY sear eeel� Inbrq. f19E oensay mlwmbmgslandala Pmleeaobn Revslalce w.ml-manor paadurncu�ndara enlrorconlneunn psrJlgM Tvm 9landwd Mw4wGr d p��. Swm Ilneorlfela0 Cau4�aslWe� vale � � �snslN) d. BbwslFl (��) C41MI) BbwsIPL � Very lace B-3 Very Sm e35 BWn 50r 0-1 ur Imso a-s soft saoba000 1 z-+ +-e tA�Nen Dense Io-ze sLwam s+n taaa nzol:a N Oensa 30-W 511t 2000 b1.A00 a-s5 Vary Oaee >50 Yay 9af 4�ObBUW IS-]Y Irua >eoao l7ESCRa%71oN FTFT h TEST AGaElICe a try masLre. al,sty, ay m the toucth I,,Idst �rnptiutno vile wrier Visible tee tl�lea. Wel LrsueAysdl Is Dd walev ale DESCRIPTION CRffFJ21A Argular Particles have sharp edges and relatively plane sides with unpdished Surfaces. Subangular Particles are similar to angular description but have nwnded edges. Subrounded Particles have Heady plane sides but have well-rounded comers and Rounded Particles have smoothly curved sides and no edges. Soil Symbols Description Key I� A C Sunlight Valley Holdings LLC 7 � � � 5810 CR 320 Modular Home Plate Garfield County, Colorado Copyright GeoStrata, 2025 Project Number: 1869-004 ��� APPENDIX C a 0 Vl .y � a d.. d LM UU �ad8 w rn U o. h 70 N LO LO o o Cl) U w z 00 w a z N y c \ o 0 C O '7 'o Ac 0 0 co 0 � coN d 0 O O 4 ti t V •may aC7 ten" N 07 Cl) O) � Q z 00 00 C {O O M -' 00 0 y � �U X a L y d En N O N a� O A H p+ e o 0 0 N CO a U 60 CL CH 50 0 � 40 w A � 30 U H Q 20 a 10 O O CL-ML 20 40 60 80 100 LIQUID LIMIT (%) Sample Location Depth (11) LL NO PL NO PI (/°) Fines (/°) Classification ■ TP-01 1.0 NP NP NP 3.0 Poolry Graded GRAVEL with sand m TP-02 1.0 26 18 8 71.0 Lean CLAY with sand f I*e A �' } N *of � � ATTERBERG LIMITS' RESULTS - ASTM D 4318 Sunlight Valley Holdings LLC 5810 CR 320 Modular Home Garfield County, Colorado Project Number: 1869-004 Plate C _ 2 U.S. SIEVE OPENING IN INCHES I U S. SIEVE NUNMERS I HYDROMETER 1 1 1M 1 4 In 1(. zn cn ;' 11■1■11III�IIIIi■i� �:ylAYv■IIVIIIIIYYIlII1111■■IIIIIII■ "� �'"�111111�1■■IIIIIII■■1111111■ .,11■■III11111■■Ili���■� � .: .11 ■■I II IIL�■■I II I 111■■ Ilia: ��■■IIII [II■ ■ li11111 ■■ :,11■■111111��■■1111111■■11111r�■�11111111■■IIIIIII■■ 11■■1111111�■®1111111■■1111[II\■1111111■■IIIIIII■■ ,11■■11i1111■■Illllll■■IIII[11■1„ 10-11111011111111101 ,11■■1111111��■Illllll■■1111111■\11111111■■1111111■■ .,11■■111111IN111111111■■1111111■■1111111■■1111111■■ 1■■■IIIIIII ■■ 1111111 ■■II 11111■■l�I11■■■1111111■■ ,11■■IIIIIII■1IIIIIII■■I111111■■11w1111■■1111111■■ ,11■■Illllll■\\IIIIIII■■11ii111■■1111[II■■1111111■■ 11■■1111111■�71i11[II■■1111111■■1111[II■■1111111■■ 11■ ■III IIII■©� II1111 ■ ■ 1111111■■ III l[11■■I I11111■ ■ 11�■I111111■■I�I1111■■I111111■■li11111■■1111111■■ 11■ ■1lM 1111■■111� �l1■ ■IIIIIII■■I111111 ■■IIIIIII■■ 11■ ■1111111■■UNION ■ UNION N 11111111101111111001 11 ■ ■IIIIIII■®I II I I114 1111111 ■ 11111111001111111001 ,11■■IIIIIII■■1111111■■�1���!�1■■IIIIIII■■IIIIIII■■ 11 ■ ■IIIIIII■■II11 [11■■ I ll l Ili i �l Ill[ I I■■i111111■■ r 11■■II11111■®II11111■■Illllll■■u�1�1111■■1111111■■ rr r r r r r r GRAIN SIZE (mm) COBBLES GRAVEL I SAND SILT OR CLAY coarse Ifine I coarse I medium I fine Sample Location Depth Classification LL PL I PI Cc I Cu ■ TP-01 1.0 Poolry Graded GRAVEL with sand NP NP NP 6.57 157.35 m TP-01 2.0 Sandy Lean CLAY TP-02 1.0 Lean CLAY with sand 26 18 8 Sample Loctaion Depth D100 D60 D30 D10 %Gravel %Sand %Silt %Clay 9 TP-01 1.0 50 20.477 6.933 0.357 76.0 21.0 3.0 m TP-01 2.0 12.5 0.093 7.0 38.0 55.0 A TP-02 1.0 19 5.0 24.0 71.0 GRAIN SIZE DISTRIBUTION - ASTM D422 Sunlight Valley Holdings LLC Plate 5810 CR 320 Modular Home Garfield County, Colorado C _ 3 Project Number: 1869-004 i 1 2 3 0 F" 4 U w 5 - 6 7 8 100 1,000 10,000 EFFECTIVE CONSOLIDATION STRESS (psfl Sample Location Depth (ft) Classification Ya�MC (pco(°/a) Inundation Load (ps fl Swell (%) Collapse NO ■ TP-01 2.0 Sandy Lean CLAY 92 5 1000 - 0.20 t %A w C MM #N 1W qW y ftv I 1 %4 1 w 1-D SWELL/COLLAPSE TEST Sunlight Valley Holdings LLC 5810 CR 320 Modular Home Garfield County, Colorado Project Number: 1869-004 Plate C — 4 0 1 2 3 4 a U , F- 5.. 6 7 8 100 1,000 10,000 EFFECTIVE CONSOLIDATION STRESS (psfl Sample Location Depth ($) Classification % cfl MC (/o) Inundation Load (psfl Swell (/o) Collapse (/o) i TP-02 1.0 Lean CLAY with sand 94 8 1000 - 3.55 1-D SWELL/COLLAPSE TEST Sunlight Valley Holdings LLC 5810 CR 320 Modular Home Garfield County, Colorado Project Number: 1869-004 Plate C - 5 it y ! APPENDIX D 01r• -�W Photo 1, S side of existing modular home at 5810 County Road 320. Approximate center of proposed modular home marked by a white painted survey stake for utility clearance in center of photo. Propane tank visible in right hand portion of photo. Looking northeast towards County Road 320 with existing modular home to be removed beyond survey stake. ftAMO%C&WfflW&AW v%-Wvv1 1 WPM Copyright GeoStrata, 2025 Site Photos Sunlight Valley Holdings LLC 5810 County Road 320 Modular Home Garfield County, Colorado Project Number: 1869-004 Plate D-1 �-�':►''y' •�#_'-R ��""a��.... �����i� _ ?.tii-,;�^':; `�r"�.'. mac• ... ~mow. Y•ION- s• `���YY -F�• � , -� ! Photo 2, SE corner of existing modular home (to be removed) in the background with septic tank access on the west side of the modular home in the foreground, looking S toward location of proposed modular home to hill referenced in Project Location and Existing Conditions (Section 2.2) in this report. Oftm Aft A% 06 Copyright GeoStrata, 2025 Site Photos Sunlight Valley Holdings LLC 5810 County Road 320 Modular Home Garfield County, Colorado Project Number: 1869-004 Pi Plate D-2 Photo 3, excavation of Test Pit No. 1 along the north side of the proposed modular home. GeoStrata attempted to excavate the test pits outside of the proposed building envelope due to the likelihood that necessary compactive effort would not be applied to the backfill of the test pits. Photo looking NE towards County Road 320. Site Photos w CIjW AM IJN Sunlight Valley Holdings LLC 5810 County Road 320 Modular Home Plate Copyright GeoStrata, 2025 Garfield County, Colorado D-3 Project Number: 1869-004 1J At ti Y� 5. �Z. � \�"�M . Li..J. ✓. F it �- r t .j. r - Photo 4, excavation of Test Pit No. 1 with S wall on the right side and E wall in the background. Gravel layers are noticeable on the S wall from 1 to 2 feet and on the S wall wrapping onto E wall from 5 to 6 feet. Test Pit No. 1 excavated to a depth of approximately 10 feet. Site Photos w C M Sunlight Valley Holdings LLC %or> %f 4%F , , , 5810 County Road 320 Modular Home Plate Copyright GeoStrata, 2025 Garfield County, Colorado D _4 Project Number: 1869-004 AN Li • '. . } . .�` I•if J CCr�y �tisf ! ��! � .4 1 Photo 5, excavation of Test Pit No. 2 along the south side of the proposed modular home. GeoStrata attempted to excavate the test pits outside of the proposed building envelope due to the likelihood that necessary compactive effort would not be applied to the backfill of the test pits. Photo looking NE towards County Road 320. Site Photos ft©Aft C Sunlight Valley Holdings LLC 5810 County Road 320 Modular Home Plate Copyright GeoStrata, 2025 Garfield County, Colorado n_C Project Number: 1869-004 J .S Photo 6, E (left), W (right), and S (background) excavation walls of Test Pit No. 2 looking to the S with the hill referenced in Project Location and Existing Conditions (Section 2.2) in this report in the background. Test Pit No. 2 excavated to an approximate depth of 5 feet. Site Photos C&W N 406 Sunlight Valley Holdings LLC v 11 %06 , %4 5810 County Road 320 Modular Home Plate Copyright GeoStrata, 2025 Garfield County, Colorado D-6 Project Number: 1869-004 APPENDIX E GeolechniCel-EfloineePing Report —� The Geoprofessional Business Association (GBA) has prepared this advisory to heir you - assutliedly a client representative - interpret and apply this geotechnical-engineering report as effectively as possible. In that way, you can benefit from a lowered exposure to problems associated with subsurface conditions at project sites and development of them that, for decades, have been a principal cause of construction delays, cost overruns, claims, and disputes. If you have questions or want more information about any of the issues discussed herein, contact your GBA-member geotechnical engineer Active engagement in GBA exposes geotechnical engineers to a wide array of risk -confrontation techniques that can be of genuine benefit for everyone involved with a construction project. Understand the Geotechnical-Engineering Services Provided for this Report GecRechnlcal-engineering services typically include the planning, collection, Interpretation, an d soalyms of exploratory data from widely spaced borings andlor test pits. Fleld data are combined with results from laboratory tests ofsoll an d rocksarmples obtained from field exploration (if appllcable),observaticros made daring, site reconnalssaace. and historical Loformatlon to form one or more models of the expected wbssu•fac; conditions beneath the site Local geology and alterations of the sitesurfa.ce and subslLrface by previous and proposed const rution are•alsr., Important considerations. Geotechnical engineers apply, their engineering training, experience, and judgment to adapt the requirements of the prospective proie:t to the sub6tirface model(s). Estimates are made of the subsurfaeeconditions that will likely beexpwedduring construction as well as the expected p.:rf•_ nw nee of foundations and other structures being planned and/or affected by construction acubJtles. The culmination of these geoteclunital-englneeAngservices Is typically a geotechnical-engineering report providing the data obtained, a discussion of the subsurface ntodel(s), the engineering an d geologic engineering assessments and analyses made, and the reronunendatloos developed to satisfy the given requirements of the project. These reports maybe titled investigations, explorations, studies, assessments, or evaluations. Regardless eftbe title used the geotecbintcal-englneerIng report is an engineering Interpretation of Ow, subsurface conditions within the, conteKl[ ofthe project and does not represent a close ertaminatlean„ systematic Inquiry, or thorough Investigation ofall site and subsurface conditions. Geotechnical-Engineering Services are Performed for Specific Purposes, Persons, and Projects, and At Specific Times Geotechnical engineers structure their services to meet the specific needs, goals, and risk managemenl preferences of their clients. A geotec[ru ca l-engineering study c•:�n ducted for a given civil engineer rMWAMO%C&WfflW&" Copyright GeoStrata, 2025 will not likely meet the needs of clyll-works constructor or even a dllferent civil engineer, Because each geokchnlcal•engineerwg study is uni qua, each geotechnical-engineering repoil is unique, prepared soldy for the client. IA]wwlse, gec4echnlcal-engineering services are performed for a specific prated and purptse. For ecample. it is unlikely thal a gocaechnical- englneertngstudv for a refrlgerawd+>tiarebouse will be the saute as our prepared for a parking garage and a few bortngs drilled during a preliminary study to evaluate site feasibility will not be adequate to develop geotechn Ica] design recommen datlons for the project Do &,I niiy ore tfi:s rep&T if your ge7tecbnlcal engineer prepared it: • for a dilTerent cllent; • for a different prt�lect or purpose; • for a different site (tha I may or may n of Include all or a portion of the original slte); or • before lntpc•rtant events occarFed at die site :-i aAtcenI to It; e.g., nnan • anode events Itke cons iruction or env Iron mental rentedlatlon, or natural events like floods, drotights, earthquakes, or grown dwater llactuations. Note, too, the iehabLllty of a geotechrrlcal-engineering report can be affected ty the passage c•f urn e, beca use of factors like ehinged suirsurfoce conditre n P. new or modified codes. standards, or regulations; or n ee,• techniques or tools. lily at4 m e tlreYeastlr:i mart in n about the cantLnued rehablhty of this rep-r t, c eat act your ge.Aechntca.l engineer before applying the recommendations In It A minor amount of additional testing or analysis after the passage of time — If any is requiredat all — could prevent major problems. Read this Report in Full Costly problems Never.cowered because those relying on a ge..Whaical- eaglneenng report did rndt read the report I n Its enitro F. Do not rely tin an ewecutive sammary. Dc,1Lj, readseleeuve elements anly AW awn ntfer to the r eporr rre.frdf. You Need to Inform Your Geotechnical Engineer About Change Your geotechnLcal engineer considered unique, project-spectfrc factors when deo.el:,ping dK-m-p (- ofstudy behind this reportand developing the coniirinatlan-dependent recommendations the report c-jnveys. Typical changes that could erode the reliability ofthis report include those that affect: • the sites size or shape; • the elevation, configuration. location, orlentati-m. function or weight of the proposed structure and the desLredperf-cmance criteria; • the composition of the design team: or . project ownership. As a generalrule,alrwys inform your geowbrilcal engineer of project or site changes — even nun or ones — and request an assessment of their impact. Tree geoiechnfozi errgiNver w a p"p ar>:nl th)s report rarer V twcepr Important Information about this Report Sunlight Valley Holdings LLC Plate 5810 CR 320 Modular Home Garfield County, Colorado E_11 Project Number: 1869-004 riesponsebU(tyorilal.:isrY}aJ-,pjv Hems thatarlse deiaase rkekx1tecknki i eugenekr wrxs Naf erufortned aiour ifeve1cpmem's the engfj*} r othey tr•ese ry idd Pique croslderea Most of the "Findings" Related in This Report Are Professional Opinions Before construction begins, geotech :Ica] engineers explorea site]; sul:4urface using various sampling and testing procedures. Qvre hmri i ertgenCON can obsetVe actual slabscl{fctce coNIMONs only of fhasespdVefie Jecanons ia4 le salr2� rfvg+ aNd rescong Js [wforoant The data derived from that sampling and tesir fig were reviewed by, c•ur ge-_-technical erngl n eer, who then applied piofesslonal tudgement to form c•phileos about subsurface conditions throughout the site Actual sltewlde•subsurface conditions maydiffer -maybe significantly- front those Indicated In this report. Confront that risk by retaining your geoteclinicai angi near to serve on the design teant through pnyiect completion to abtakn Infonued guidance quickly, whenever needed. This Report's Recommendations Are Confirmation -Dep en dent The reoamir lendations Included In this report — Including any options or alternatives - are confirmstion-dependent. In other words, they are not final, because the geotechnical engineer who devel:)W them relied heavily r-a Judgement and opinion to do so. Your geotech-mical engineer can finalize the recommendations mvfy Brie- obser-i•ftig+actual subsro face cond'Dom exposed during construction. If through observation your geotechnical engneer confirms that the conditions assumed to exist actually do exist. the recommendations can be relied upon, assuming no other changes have occurred: 3Pvegeombskrd ergbiew wYna prmpared fbfs apart csinnof iissiurle rdspons00(Jrcrrlabfllty.fv-coWmatkvrdeptvidlexrrevwntneradatkvtsyy1a fial to ivragn diaterlgrtiter tope;tfsrtn coxsf -iA-tdoN obsrzntlon. This Report: Could Be Misinterpreted 01ho design profess) orals' misinterpretation ofgeotechnlcal- ngi near Ing repor is has resulted In costly problems. Confront that risk by having your geotechnical engineer serve as a continLwig member of the design team, to: • confer with other design -team members: • help deNWop specifications: • review pertinent elements of other design professionals' plans and specifications: and • be avallablewheneaurgeotechnkal-engineermgguidanceisnee led. You should also confront the risk of can structors misinterpreting this report Do so by retaining your geotechnical engineer to participate in prebid and preconstructwm conferences and to perform con structlon- phase observation s. Give Constructors a Complete Report and Guidance &are owners an d design processionals mistaken] v bell eve they tan sblft unanticipated-subsurfacc- omdttonsI labilINI constructors by tinilting die Inf •rrnatic•n they pr ,.1de for bid preparation. T_- help prevent time costly, contentious problems this practice has caused, include the complete geotechnical-engineering report, along with any attachments or sppen dices. with your contract docuuvents, bat K certi;A; to dote con sptuouslythatyorr've fn. wleiftheutatErealfx JrafoenaifINpeposeN- oxlyt To avoid misunderstanding, yeas may also want to note that infc nnallonal pLu poses' in e am cm-nstructors have no right to rely on t he Interpretativns. opintons, c onclus ins, or recoinmendatEt ns In the report. Rc certaln tliai construclots know they htay ]tarn about spccltic proaen iequlrements. Including selected frtni the report, ordy from the designdrawings and specifications. Remind cconstructors that they may perfornn their own studies Iftbey wan t to, and cti scar a to al;owe rldvlgh tw.v to perm It therm to do so. Only then might you be in a position to give constructors the Information available to you,wblle requiring them to at least share softie of the finarido] responsibilities stemnung from Lima oticipated con dition s. Conducti ng prebl d and preconstruction conferences ca n also be valuable In this respEx-t. Read Responsibility Provisions Closely Sortie client representatives, design profmionals, and constructors do not realize that geotechnical engineering is fax less exact than other engineering dlscp[lnts, Th is happens 111 pact because v-1I an d wd'- Can project sites are typically heterugena>usand ti�i rnanufsctumd ntate nals with well- dAned engincertng proper lies Ilke steel andc_mcrete.7ltat lack of tmdersianding has netrtured unreaIIsuc expectations that have resuilted in disappointments. delays, cost overruns, claims, and asp Ittes. To confront that risk, ge-:,technlcal engineers commonly include explanatory pmVIAotns In thelI reports. Sometimes labeled`Umitatlons, many of these provisions Indicatewheregeotechnlcal engineers responsibilities begin andend, to help others recognize their own responsibilities and risks. Read thdse frrorlsfoss rdoseiy, Ask question s Your geot-echnIca] engineer should respond fully and frankly Geoenvironmental Concerns Are Rol Covered The personnel, equipment, and tediniques used to perform an environments study - e.g., a "phase -one" or"phase-two" environmental site assessment - differ significantly frov those used to perform a geotechnical-engineering A*. For that reason, a geatechn ]cal -engineering report does not usually provide environmental findirigs.a-nduslons,or re\N-jurtiendaticns; e.g., about the Itlar?]lhoodofencoantering andlarVround st "ge tams or regulated contaminants. UmmOdPated wbsul�ice t7wU'annrrNralproblerNs hair leaf to praJdxt�Erliwti�. Ifyau have not obtained your uwu environmental Information about the protect site, ask your geotechnical consultant for a recommendailon on how to find environmental risk -management guidance. Obtain Professional Assistance to Deal with Moisture Infiltration and Mold While your geotechnical engineer may have addressed gro andwater, water Infiltration, or similar Issues In this report, the engineer's sefviceswere not designed:, conducted. or Intended to prevent migration of moisture - Including water vapor - from the soil through building slabs and walls and Into the building Interior, where It can cause mold growth and material -performance deficiencies. Accordingly, proper impfemenfation of fhe geaiechisicar engineers lieconinietieiuidoms wiling op ilselfbe sufricienr to prevem rrraistwre infiMarim. Cat frvnr tire risk of rivoisrare hifidrnntfore by IncIuding bullding-envelope _a mold spaclalists on the R-Mgii ILam. Geolechrvicalenginet•rxare Misr buiraling-tv,velope orn,owspr.rarias. GeAGEOPROFESSIONAL BUSINESS ASSOCIATION Telephone: 3011565 -273 3 e-mail: inlioCogeoprofessional.org w Arw.geoprofessional.org coprrighi ,o 19 k+-GtoprciessLxaal BusirienAssodatlon I GEA.). 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