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HomeMy WebLinkAboutGEOTECHNICAL REPORT 660 Community Dr Community Center 2016-04-29 GEOTECHNICAL SUBSURFACE EXPLORATION REPORT ESTES VALLEY COMMUNITY CENTER COMMUNITY DRIVE AND MANFORD DRIVE ESTES PARK, COLORADO EEC PROJECT NO. 1162032 Prepared for: Estes Valley Recreation and Park District c/o RLH Engineering, Inc. 541 East Garden Drive, Unit S Windsor, Colorado 80550 Attn: Mr. Chuck Jordan (cjordan@rlhengineering.com) Prepared by: Earth Engineering Consultants, LLC 4396 Greenfield Drive Windsor, Colorado 80550 April 29, 2016 Estes Valley Recreation and Park District c/o RLH Engineering, Inc. 541 East Garden Drive, Unit S Windsor, Colorado 80550 Attn: Mr. Chuck Jordan (cjordan@rlhengineering.com) RE: Geotechnical Subsurface Exploration Report Estes Valley Community Center Community Drive and Manford Drive Estes Park, Colorado EEC Project No. 1162032 Mr. Jordan: Earth Engineering Consultants, LLC (EEC) personnel have completed the geotechnical subsurface exploration requested for the proposed Estes Valley Community Center planned for construction adjacent to the north perimeter of the existing Aquatics Center, east of Community Drive and south of Manford Drive in Estes Park, Colorado. Thirteen (13) soil borings extending to depths of approximately 10 to 25 feet below present site grades were advanced in proposed improvement areas to develop information on existing subsurface conditions. Results of those borings and diagrams indicating the approximate improvement and boring locations are provided with this report. This study was completed in general accordance with our proposal dated March 28, 2016. In summary, the subsurface materials encountered in the test borings generally consisted of decomposed granite bedrock elevations to competent granite with increased depths. However, a portion of those materials may be lower density fill material placed during previous site improvements. Based on results of the field borings and laboratory testing, we anticipate the proposed building could be supported on conventional footing foundations bearing on the natural decomposed granite bedrock. In areas where lower density existing fill materials are located below design bearing footing foundations should be extended to greater depths to be supported on more competent decomposed granite material. The presence of existing fill materials on the 4396 G REENFIELD D RIVE W INDSOR, C OLORADO80550 (970) 545-3908 FAX (970) 663-0282 GEOTECHNICAL SUBSURFACE EXPLORATION REPORT ESTES VALLEY COMMUNITY CENTER COMMUNITY DRIVE AND MANFORD DRIVE ESTES PARK, COLORADO EEC PROJECT NO. 1162032 April 29, 2016 INTRODUCTION The geotechnical subsurface exploration requested for the proposed Estes Valley Community Center planned for development adjacent to the northern perimeter of the existing Aquatic Center east of Community Drive and south of Manford Drive in Estes Park, Colorado, has been completed. Eleven (11) soil borings extending to depths of approximately 15 to 25 feet below present site grades were advanced in the proposed Community Center building addition area and north detention area to develop information on existing subsurface conditions. Two (2) other borings to depths of approximately10 feet were completed within proposed pavement areas. Individual boring logs and a boring location diagram indicating the approximate improvements and boring locations are provided with this report. The new Estes Valley Community Center will be located south of Manford Drive and east of Community Drive adjacent to the north of the existing Estes Park Aquatics Center. The area to the east includes the Estes Park school complex. A previous building footprint within the area of the planned pavement improvement was recently razed. However, the existing concrete foundation and floor slab are still in-place. A diagram indicating the approximate Community Center layout is included with this report. As we understand, the new Estes Valley Community Center will be a multi-use recreation and community center facility with a new leisure pool, gymnasium and fitness center in addition to community meeting facilities. The proposed building will be 2-story with the lower level cut into the subgrade to the south becoming a full-story below grade adjacent to the existing at-grade aquatics center. The north entry to the building will be at approximate existing grade. Maximum cuts within the building area are expected to be on the order of 10 feet below current site grades. Earth Engineering Consultants, LLC EEC Project 1162032 April 29, 2016 Page 2 Foundation loads for the proposed building are anticipated to be light to moderate with continuous wall loads less than 2 kips per lineal foot and maximum column loads of approximately 300 kips including full dead and live loads. Floor loads are expected to be light. Retaining walls will be constructed to separate upper and lower floor levels adjacent to the leisure pool and separate the upper and lower level entrances outside of the building footprint. It is anticipated the new site pavements will be used by low to moderate volumes of light vehicles. The purpose of this report is to describe the subsurface conditions encountered in the test borings, analyze and evaluate the test data and provide geotechnical recommendations concerning design and construction of the proposed building and site improvements. EXPLORATION AND TESTING PROCEDURES The boring locations were selected by others and established in the field by Earth Engineering Consultants, LLC (EEC) personnel by pacing and estimating angles from identifiable site features. The approximate boring locations are indicated on the attached boring location diagram. Existing ground surface elevations were interpolated at each boring location from the topographic contours presented on the “Sketch Plan Diagram” provided in the project package submitted to our attention from RLH Engineering, (please refer to Figure No. 3 included in the Appendix of this report). The locations of those borings and estimated ground surface elevations should be considered accurate only to the degree implied by the methods used to make the field measurements. Six (6) soil borings were previously completed within the proposed building area as a part of a geotechnical exploration in 2006 for various building additions at the Estes Park school complex. Four (4) other soil borings were completed at that time in the general area of the new pavements to the east of the proposed community center. Results of the prior borings were reviewed as a part of our analysis for this project. The borings for the proposed community center were performed using a truck mounted, CME-75 drill rig equipped with a hydraulic head employed in drilling and sampling operations. The boreholes were advanced using 4-inch nominal diameter continuous flight augers. Samples of the subsurface materials encountered were obtained using split-barrel and California barrel sampling procedures in general accordance with ASTM Specifications D1586 and D3580, respectively. Earth Engineering Consultants, LLC EEC Project 1162032 April 29, 2016 Page 3 In the split-barrel and California barrel sampling procedures, standard sampling spoons are driven into the ground by means of a 140-pound hammer falling a distance of 30 inches. The number of blows required to advance the samplers is recorded and is used to estimate the in-situ relative density of cohesionless materials and, to a lesser degree of accuracy, the consistency of cohesive soils and hardness of weathered bedrock. Relatively intact samples of the subsurface materials were obtained in the California barrel sampler. All samples obtained in the field were sealed and returned to our laboratory for further examination, classification and testing. At boring locations B-8 and B-11, field slotted 1½ inch diameter PVC piezometers were installed in the open bore holes prior to backfilling. The piezometer locations were registered with Colorado Division of Water Resources (CDWR) in accordance with Colorado State Regulations. The piezometers will need to be removed within one year of installation and notification of the removal/abandonment provided to CDWR. If requested, we can provide assistance with the abandonment and/or reporting. All recovered samples were tested in the laboratory for moisture content and the unconfined strength of appropriate samples was estimated using a calibrated hand penetrometer. Atterberg limits and washed sieve analysis tests were completed on selected samples to establish the plasticity and percentage of fines in the subgrade materials. Swell/consolidation tests were completed on selected samples to evaluate the subgrade tendency to swell with increased moisture content at current moisture and density conditions. Soluble sulfate tests were completed on four (4) samples to help assess the potential for sulfate attack on site-cast concrete. Results of the outlined tests are indicated on the attached boring logs and summary sheets. As part of the testing program, all samples were examined in the laboratory and classified in general accordance with the attached General Notes and the Unified Soil Classification System, based on the soils’ texture and plasticity. The estimated group symbol for the Unified Soil Classification System is indicated on the boring logs and a brief description of that Classification System is included with this report. Classification of the bedrock was based on visual and tactual observation of disturbed samples and auger cuttings. Coring and/or petrographic analysis may reveal other rock types. Earth Engineering Consultants, LLC EEC Project 1162032 April 29, 2016 Page 4 SITE AND SUBSURFACE CONDITIONS The Estes Valley Community Center will be located east of Community Drive and south of Manford Drive at the west side of the Estes Park school complex. The Community Center will be constructed adjacent to the north of the Aquatics Center. The site slopes down to the north from the Aquatic Center adjacent to Community Drive and is predominately an existing pavement area. A former building was located in the proposed pavement area but was razed prior to our field exploration. The surface materials at the boring locations generally consisted of a relatively thin mantle of gravel surfacing or pavement sections ranging from approximately 2 to 3½ inches of asphalt with a thin gravel base. The materials immediately beneath gravel and/or asphalt consisted of decomposed granite. The very near surface decomposed granite may include areas of previously placed decomposed granite fill. The decomposed granite was generally moderately hard although looser zones were observed near surface at some boring locations. Decomposed granite becoming more competent with depth, extended to the bottom of all borings at depths ranging from approximately 10 feet to 25 feet below present site grades. The stratification boundaries indicated on the boring logs represent the approximate locations of changes in soil and rock types; in-situ, the transition of materials may be gradual and indistinct. GROUNDWATER CONDITIONS Observations were made while drilling and after completion of the borings to detect the presence and depth to hydrostatic groundwater. In addition, water levels were observed in the two piezometers immediately after and approximately one week after drilling. No free water was observed in most of the borings at the time of drilling. However, free water was observed in the vicinity of borings B-7 thru B-9 and B-11 with water levels measured at depths of approximately 11 to 17 feet below ground surface. PVC piezometers were installed in boring B-8 and B-11, and subsequent measurements a week later indicated groundwater levels at depths of 11 to 13 feet. Fluctuations in groundwater levels can occur over time depending on variations in hydrologic conditions and other conditions not apparent at the time of this report. Earth Engineering Consultants, LLC EEC Project 1162032 April 29, 2016 Page 5 Perched water may also be encountered in soils overlying less permeable bedrock and may be encountered in looser fill materials overlying the competent bedrock and/or within fractured zones of bedrock. The location and amount of perched water can also vary over time depending on variations in hydrologic conditions and other conditions not apparent at the time of this report. ANALYSIS AND RECOMMENDATIONS Swell/Consolidation Test Results As a part of our laboratory testing, we conducted seven (7) swell/consolidation tests on samples of the decomposed granite bedrock. The swell index values for the samples analyzed revealed slight consolidation to low swell characteristics when inundated with water and pre-loaded at 150 psf and 500 psf, as well as exhibiting a slight tendency to hydro-compact and consolidate with increased loads. Results of the laboratory swell tests are indicated below in Table I, on the attached boring logs, and on the enclosed summary sheets. TABLE I - Swell Consolidation Test Results BoringDepth, In-Situ Moisture Dry Density, Inundation Swell Index, Material Type No. ft.Content, %PCFPressure, psf (+/-) % B-1 2 Decomposed Granite 8.2 118.1 500(-) 0.2 B-2 2 Decomposed Granite 9.7 122.8 500(-) 0.1 B-4 4 Decomposed Granite 11.2 124.9 5000.0 B-7 2 Decomposed Granite 11.0 115.4 500(-) 0.1 B-8 2 Decomposed Granite 11.0 118.0 500(-) 0.1 B-9 2 Decomposed Granite 8.7 122.9 5000.0 B-12 2 6.1 119.6 150(+) 0.5 Decomposed Granite The Colorado Association of Geotechnical Engineers (CAGE) uses the following information to provide uniformity in terminology between geotechnical engineers to provide a relative correlation risk performance to measured swell. “The representative percent swell values are not necessarily measured values; rather, they are a judgment of the swell of the soil and/or bedrock profile likely to influence slab performance.” Geotechnical engineers use this information to also evaluate the swell potential risks for foundation performance based on the risk categories. Earth Engineering Consultants, LLC EEC Project 1162032 April 29, 2016 Page 6 TABLE II: Recommended Representative Swell Potential Descriptions and Corresponding Slab Performance Risk Categories Slab Performance Risk Representative Percent Swell Representative Percent Swell Category (500 psf Surcharge) (1000 psf Surcharge) Low0 to < 3 0 < 2 Moderate 3 to < 5 2 to < 4 High 5 to < 8 4 to < 6 Very High > 8 > 6 Based on the laboratory test results, the in-situ samples of decomposed bedrock were generally in the low risk range. Site Preparation and General Considerations Decomposed granite was encountered at relatively shallow depths in most borings. It is our expectation the building and site improvements at most locations could be supported on the natural, in-situ decomposed granite. However, on the north side of the site, lower relative densities in the tested materials indicate that the in-place materials are more likely fill materials consisting of decomposed granite fill. Other locations on the site may also consist of, at least near surface, previously placed overlot fill to develop existing site grades. Since those fill materials are also decomposed granite, differentiation between fill and native soils may be difficult. Establishing that the footing foundations are supported on suitable strength natural materials will be critical to functioning of the footing foundations for support of the proposed structure. Extending footings to bear below any fill materials on the north side of the site may be required to develop foundation bearing or use of alternative deeper foundations to extend to more competent decomposed granite may be considered. Recommendations are provided below for support of footing foundations on native material. Recommendations for use of deeper foundations can be provided if needed. Excavation penetrating the very dense/more competent granite with increase depth will require the use of specialized heavy-duty equipment such as a rock hammer, core barrel and/or possibly a controlled blasting program to achieve final design elevations. Consideration should be given to obtaining a unit price for difficult excavation in the contract documents for the project. Earth Engineering Consultants, LLC EEC Project 1162032 April 29, 2016 Page 7 Based on our understanding of the proposed development, it appears minor to moderate amounts of cut/fill operations on the order of approximately 0 to 10 feet (+/-) will be necessary to achieve design grades. After stripping and completing all cuts and prior to placement of any moisture- conditioned fill material and/or site improvements, we recommend the exposed soils. Where applicable, be scarified to a minimum depth of 9-inches, adjusted in moisture content to within ±2% of standard Proctor optimum moisture content and compacted to at least 95% of the material's standard Proctor maximum dry density as determined in accordance with ASTM Specification D698. If, after the various cuts as required, are to extend into the undisturbed granite bedrock, scarification and recompaction of the granite bedrock would not be necessary. Fill soils required to develop the pavement and site subgrades should consist of approved, low- volume-change materials, which are free from organic matter and debris. It is our opinion the on-site decomposed granite could be crushed and used as fill in these areas, provided fragments larger than 3 inches are removed and adequate moisture treatment and compaction procedures are followed. Approved structural fill material graded similarly to a CDOT Class 5, 6 or 7 aggregate base with sufficient fines to prevent ponding of water within the fill could also be considered. We recommend the fill soils be placed in loose lifts not to exceed 9-inches thick and adjusted in moisture content and compacted as recommended for the scarified soils. FOOTING FOUNDATIONS-NATIVE DECOMPOSED GRANITE We anticipate footing foundations at most design bearing depths will be supported on natural decomposed granite. For design of footing foundations bearing on the natural moderately dense to dense decomposed granite, we recommend using a net allowable total load soil bearing pressure not to exceed 5,000 psf. The net bearing pressure refers to the pressure at foundation bearing level in excess of the minimum surrounding overburden pressure. Total load should include full dead and live loads. In areas where the footing foundation bearing elevations would be above the competent decomposed granite, we recommend those footings be extended to bear on competent in-situ decomposed granite. From the boring logs, looser materials were observed in borings B-2, B-4, B-7 and B-8 extending to depths of approximately 3 to 6 feet. Shallow depth of looser material may be encountered at other locations. As the building is cut into the subgrade, the bearing elevations will naturally extend to below any surficial loose materials. Extra care should be taken on the north end of the building where shallow cuts will occur to see that footings extend Earth Engineering Consultants, LLC EEC Project 1162032 April 29, 2016 Page 8 to competent bearing materials. The allowable bearing pressure may be increased by 1/3 for short term wind or similar loading. Exterior foundations and foundations in unheated areas should be located at least 3 feet below adjacent exterior grade to provide frost protection. We recommend formed continuous footings have a minimum width of 12 inches and isolated column foundations have a minimum width of 24 inches. Trenched foundations or grade beam foundations should not be used to allow for more thorough evaluation of anticipated bearing soils at the time of construction. Care should be taken to thoroughly evaluate anticipated bearing materials at the time of construction. With former site grading, zones of fill and backfill should be expected and caution should be taken to extend footing foundations through those materials. Particular care would be necessary immediately adjacent to the existing structures or former structures where backfill materials would have been placed. The depth of any site fill materials at the boring locations did not appear to be greater than a few feet. All footings for the structure should bear on uniform/similar materials to reduce the potential for differential movement between soil types. We estimate the long term-settlement of footing foundations designed and constructed as outlined above would be less than ½ inch. Differential settlement can occur between the new building and the existing Aquatics Center with the total differential settlement approaching the anticipated total settlement of the new footings. Seismic The site soil conditions consist of surface to near surface decomposed granite. For those site conditions, the 2012 International Building Codes indicates a Seismic Site Classification of C. Floor Slab/Pavement/Flatwork Subgrades Any existing pavements, and any vegetation and/or topsoil should be removed from beneath the proposed floor slab, pavement or flatwork areas. After stripping and completing all cuts and prior to placement of any fill, floor slabs, pavements or flatwork, we recommend the in-place materials be proofrolled with heavy construction equipment to help locate any soft or loose materials in the exposed subgrades. Particular care should be taken in the former building footprint where backfill would be expected and to the north end of the new structure where Earth Engineering Consultants, LLC EEC Project 1162032 April 29, 2016 Page 9 minimal cuts are expected. In those areas, it may be necessary to remove and replace the backfill materials to develop suitable support for the new floor slabs, pavements or flatwork. After stripping and completing all cuts including removal of existing fill, and prior to placement of floor slabs or flatwork, we recommend the top 6 inches of the exposed subgrades be scarified and recompacted as outlined for fill placement. In areas where more than 6 inches of fill will be placed, scarification recompaction of the decomposed granite subgrades would not be required. We recommend fill materials required to develop the subgrades consist of approved, low-volume change materials which are free from organic matter and debris. The site decomposed granite could be used for fill in these areas. We recommend those fill materials be placed in loose lifts not to exceed 9 inches thick, adjusted in moisture content and compacted to at least 95% of the material’s maximum dry density as determined in accordance with ASTM Specification D698, the standard Proctor procedure. The moisture content of the decomposed granite should be adjusted to a workable moisture at the time of placement. A modulus of subgrade reaction of 200 pci could be used for design of floor slabs supported on decomposed granite fill or reworked subgrade materials. Although a gravel bedding would not be required beneath the floor slabs to provide floor slab support, a sand or gravel leveling course could be considered. In addition, an approximate vapor barrier should be used to inhibit moisture migration through the slab; however, care would be necessary to minimize potential for curling of the floor slab concrete. Positive drainage should be developed away from the building and pavements to reduce potential for wetting of the bearing soils or subgrades and/or infiltration of water into the building area. Typically, a minimum slope away from the building of 1 inch per foot for the first 10 feet is recommended. Flatter slopes may be used in flatwork areas. Below Grade Walls / Retaining Walls - Lateral Earth Pressures Coefficient values for backfill with anticipated types of soils for calculation of active, at-rest and passive earth pressures are provided in the table below. Equivalent fluid pressure is equal to the coefficient times the appropriate soil unit weight. As appropriate, buoyant weights and hydrostatic pressures should be considered. Those coefficient values are based on horizontal Earth Engineering Consultants, LLC EEC Project 1162032 April 29, 2016 Page 10 backfill with backfill soils consisting of essentially granular decomposed granite materials and/or more competent granite bedrock or imported structural fill material with friction angles of at least 30 to 35 degrees respectively. The assumed values should be verified through laboratory testing. For the at-rest and active earth pressures, slopes away from the structure would result in reduced driving forces with slopes up away from the structures resulting in greater forces on the walls. The passive resistance would be reduced with slopes away from the wall. The top 30- inches of soil on the passive resistance side of walls could be used as a surcharge load; however, should not be used as a part of the passive resistance value. Frictional resistance is equal to the tangent of the friction angle times the normal force. Table III: Lateral Earth Pressure Coefficients Soil Type On-Site Decomposed Granite Imported Granular Structural Fill Wet Unit Weight 125 135 Saturated Unit Weight 135 140 Friction Angle () – (assumed) 30° 35° Active Pressure Coefficient 0.33 0.27 At-rest Pressure Coefficient 0.50 0.43 Passive Pressure Coefficient 3.0 3.70 Surcharge loads or point loads placed in the backfill can also create additional loads on below grade walls. Those lateral pressures should be evaluated on an individual basis. The outlined lateral earth values do not include factors of safety nor allowances for hydrostatic loads. Care should be taken to develop appropriate drainage systems behind below grade walls to eliminate potential for hydrostatic loads developing on the walls. Those systems would likely include perimeter drain systems extending to sump areas or free outfall where reverse flow cannot occur into the system. Where necessary, appropriate hydrostatic load values should be used for design. Perimeter Drainage Systems Groundwater and/or the presence of a water surface was encountered at various boring locations across the building footprint at approximate depths of 11 to 17 feet below site grades. Therefore, full depth basement construction is considered acceptable on the site provided the lower level slab is placed approximately 3 feet above the maximum anticipated rise of groundwater and a dual interior and exterior perimeter drainage system(s) are installed. Due to the potential for perched water to develop on the weathered granite bedrock stratum and infiltrate Earth Engineering Consultants, LLC EEC Project 1162032 April 29, 2016 Page 11 into the basement area, consideration should be given to the installation of an exterior perimeter drainage system around the foundation system. Perched groundwater/surface infiltration may occur at times since the on-site materials or foundation backfill material may be permeable while the underlying granite bedrock may be considered as relatively impermeable and would tend to trap water. Completion of site development, including installation of landscaping and irrigation systems, will likely lead to perched groundwater development. The following information should also be considered, which as previously mentioned, would be to install an interior and exterior perimeter drainage system for the proposed building. To reduce the potential for groundwater to enter the lower level/basement area 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 following provides conceptual design recommendations for interior and exterior perimeter drainage systems. The underslab 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 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 underslab 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 6-inch thickness of free-draining gravel meeting the specifications of ASTM C33, Size No. 57 or 67 or equivalent. Cross- connecting drainage pipes should be provided beneath the slab at minimum 15-foot intervals, and should discharge to the perimeter drainage system. Sizing of drainage pipe will be dependent upon groundwater flow into the dewatering system. Groundwater flow rates will fluctuate with permeability of the soils and/or weathered granite bedrock to be dewatered and the depth to which groundwater may rise in the future. Pump tests to determine groundwater flow rates are recommended in order to properly design the system. For preliminary design purposes, the drainage pipe, sump and pump system should be sized for a -3 projected flow of 0.5 x 10 cubic feet per second (cfs) per lineal foot of drainage pipe. Earth Engineering Consultants, LLC EEC Project 1162032 April 29, 2016 Page 12 To reduce the potential for surface water infiltration from impacting foundation bearing soils and/or entering any planned below grade portion of the structure, installation of an exterior perimeter drainage system is also recommended. This drainage system should be constructed around the exterior perimeter of the lower level/below grade foundation system, and sloped at a minimum 1/8 inch per foot to a suitable outlet, such as a sump and pump system. The exterior 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. Gravel should extend a minimum of 3 inches beneath the bottom of the pipe, and at least 2 feet above the bottom of the foundation wall. The system should be underlain with a polyethylene moisture barrier, sealed to the foundation walls, and extended at least to the edge of the backfill zone. The gravel should be covered with drainage fabric prior to placement of foundation backfill. Pavements Subgrades for site pavements should be prepared as outlined in the section titled “Site Preparation and General Considerations”. In addition, according to Larimer County Urban Area Street Standards (LCUASS), a minimum 3-foot separation between bottom of pavement section and undisturbed bedrock should be provided. However this is not necessarily a jurisdictional project; therefore this concern may be waived at the owner’s discretion. If the owner elects to generally comply with LCUASS; depending of final site grades, overexcavation and replacement of decomposed granite may be required to maintain the 3-foot separation. Backfilled materials should be prepared and placed as outlined in the section titled “Site Preparation and General Considerations”. In general, site pavement will be used by low volume automobiles and possibly light trucks. We expect the site pavements will include areas designated for low volume automobile and light truck traffic. We are using an assumed equivalent daily load axle (EDLA) rating of 10. Proof rolling and recompacting the subgrade is recommended immediately prior to placement of the aggregate road base section and selected pavement section. Soft or weak areas delineated by the proof rolling operations should be undercut or stabilized in-place to achieve the appropriate subgrade support. Based on the subsurface conditions encountered at the site, and the laboratory Earth Engineering Consultants, LLC EEC Project 1162032 April 29, 2016 Page 13 test results, it is recommended the on-site private drives and parking areas be designed using an R-value of 25. Hot Mix Asphalt (HMA) underlain by crushed aggregate base course, a full-depth HMA section, and non-reinforced concrete pavement could be considered for the proposed on-site paved sections. HMA pavements may show rutting and distress in areas of heavy truck traffic or in trash truck loading and turning areas. Concrete pavements should be considered in those areas. Pavement design methods are intended to provide structural sections with adequate thickness over a particular subgrade such that wheel loads are reduced to a level the subgrade can support. The support characteristics of the subgrade for pavement design do not account for shrink/swell movements of an expansive clay subgrade or consolidation of a wetted subgrade. Thus, the pavement may be adequate from a structural standpoint, yet still experience cracking and deformation due to shrink/swell related movement of the subgrade. It is, therefore, important to minimize moisture changes in the subgrade to reduce shrink/swell movements. Recommended pavement sections are provided below in TABLE IV. The hot bituminous pavement (HBP) could be grading SX (75) or S (75) with PG 58-28 oil. The HMA should be designed in accordance with LCUASS design criteria. HMA should be compacted to achieve 92 to 96% of the mix’s theoretical maximum specific gravity (Rice Value). The aggregate base should be Class 5 or Class 6 base. Portland cement concrete for pavements should be a pavement design mix with a minimum 28-day compressive strength of 4000 psi and should be air entrained. TABLE IV - RECOMMENDED MINIMUM PAVEMENT SECTIONS 18-kip EDLA 10 to 20 18-kip ESAL 73,000 Reliability 75% Resilient Modulus (R-Value = 25) 5816 psi PSI Loss 2.5 Design Structure Number 2.18 to 2.43 Composite: Option A Hot Mix Asphalt 4" @ 0.44 = 1.76 Aggregate Base Course 6" @ 0.11 = 0.66 Structure Number (2.42) Full-Depth HMA Section: Option B Hot Mix Asphalt 5-1/2" @ 0.44 = 2.42 Structure Number (2.42) PCC (Non-reinforced) – placed on a stable subgrade 5-1/2" Earth Engineering Consultants, LLC EEC Project 1162032 April 29, 2016 Page 14 The recommended pavement sections are minimums and periodic maintenance should be expected. Longitudinal and transverse joints should be provided as needed in concrete pavements for expansion/contraction and isolation. The location and extent of joints should be based upon the final pavement geometry. Sawed joints should be cut in general accordance with ACI recommendations. All joints should be sealed to prevent entry of foreign material and dowelled where necessary for load transfer. Since the decomposed granite bedrock on the site has some consolidation potential, pavements could crack in the future primarily because of the volume change of the soils when subjected to an increase in moisture content to the subgrade. The cracking, while not desirable, does not necessarily constitute structural failure of the pavement. The collection and diversion of surface drainage away from paved areas is critical to the satisfactory performance of the pavement. Drainage design should provide for the removal of water from paved areas in order to reduce the potential for wetting of the subgrade soils. Long- term pavement performance will be dependent upon several factors, including maintaining subgrade moisture levels and providing for preventive maintenance. The following recommendations should be considered the minimum: The subgrade and the pavement surface should be adequately sloped to promote proper surface drainage. Install pavement drainage surrounding areas anticipated for frequent wetting (e.g. garden centers, wash racks) Install joint sealant and seal cracks immediately, Seal all landscaped areas in, or adjacent to pavements to minimize or prevent moisture migration to subgrade soils; Placing compacted, low permeability backfill against the exterior side of curb and gutter; and, Placing curb, gutter, and/or sidewalk directly on approved proof rolled subgrade soils. Earth Engineering Consultants, LLC EEC Project 1162032 April 29, 2016 Page 15 Preventive maintenance should be planned and provided for through an on-going pavement management program. Preventive maintenance activities are intended to slow the rate of pavement deterioration, and to preserve the pavement investment. Preventive maintenance consists of both localized maintenance (e.g. crack and joint sealing and patching) and global maintenance (e.g. surface sealing). Preventive maintenance is usually the first priority when implementing a planned pavement maintenance program and provides the highest return on investment for pavements. Prior to implementing any maintenance, additional engineering observation is recommended to determine the type and extent of preventive maintenance. Site grading is generally accomplished early in the construction phase. However as construction proceeds, the subgrade may be disturbed due to utility excavations, construction traffic, desiccation, or rainfall. As a result, the pavement subgrade may not be suitable for pavement construction and corrective action will be required. The subgrade should be carefully evaluated at the time of pavement construction for signs of disturbance, such as but not limited to drying, or excessive rutting. If disturbance has occurred, pavement subgrade areas should be reworked, moisture conditioned, and properly compacted to the recommendations in this report immediately prior to paving. Please note that if during or after placement of the initial lift of pavement, the area is observed to be yielding under vehicle traffic or construction equipment, it is recommended that EEC be contacted for additional alternative methods of stabilization, or a change in the pavement section. Water Soluble Sulfates The water soluble sulfate (SO) testing of the on-site overburden and bedrock materials taken 4 during our subsurface exploration at varying depths are provided in the table below. Based on the reported sulfate content test results, this report includes a recommendation for the CLASS or TYPE of cement for use for contact in association with the on-site subsoils. TABLE II - Water Soluble Sulfate Test Results Soluble Sulfate Content Soluble Sulfate Content Sample Location Description (mg/kg)(%) B-2 @ 4’ Decomposed Granite 360 0.04 B-5 @ 4' Decomposed Granite 260 0.03 B-11 @ 4' Decomposed Granite 290 0.03 B-13@ 2' Decomposed Granite 230 0.02 Earth Engineering Consultants, LLC EEC Project 1162032 April 29, 2016 Page 16 Based on the results as presented in table above, ACI 318, Section 4.2 indicates the site decomposed granite bedrock generally was a low risk of sulfate attack on Portland cement concrete. Therefore Class 0 (TYPE I/II cement) could be used for concrete on and below site grade within the overburden soils and/or bedrock. Foundation concrete should be designed in accordance with the provisions of the ACI Design Manual, Section 318, Chapter 4. These results are being compared to the following table. TABLE III - Requirements to Protect Against Damage to Concrete by Sulfate Attack from External Sources of Sulfate Water-soluble sulfate (SO4) Water-cement ratio, Cementitious material Severity of Sulfate exposure in dry soil, percent maximumRequirements Class 0 0.00 to 0.10% 0.45 Class 0 Class 1 0.11 to 0.20% 0.45 Class 1 Class 2 0.21 to 2.00% 0.45 Class 2 Class 3 2.01 of greater 0.45 Class 3 GENERAL COMMENTS The analysis and recommendations presented in this report are based upon the data obtained from the soil borings performed at the indicated locations and from any other information discussed in this report. This report does not reflect any variations which may occur between borings or across the site. The nature and extent of such variations may not become evident until construction. If variations appear evident, it will be necessary to re-evaluate the recommendations of this report. It is recommended that the geotechnical engineer be retained to review the plans and specifications so that comments can be made regarding the interpretation and implementation of our geotechnical recommendations in the design and specifications. It is further recommended that the geotechnical engineer be retained for testing and observations during earthwork and foundation construction phases to help determine that the design requirements are fulfilled. This report has been prepared for the exclusive use of Estes Valley Recreation and Park District c/o RLH Engineering, Inc. for specific application to the project discussed and has been prepared in accordance with generally accepted geotechnical engineering practices. No warranty, express or implied, is made. In the event that any changes in the nature, design or location of the project as outlined in this report are planned, the conclusions and recommendations contained in this Earth Engineering Consultants, LLC EEC Project 1162032 April 29, 2016 Page 17 report shall not be considered valid unless the changes are reviewed and the conclusions of this report modified or verified in writing by the geotechnical engineer. DRILLING AND EXPLORATION DRILLING&SAMPLINGSYMBOLS: SS:SplitSpoon13/8"I.D.,2"O.D.,unlessotherwisenotedPS:PistonSample ST:ThinWalledTube2"O.D.,unlessotherwisenotedWS:WashSample R:RingBarrelSampler2.42"I.D.,3"O.D.unlessotherwisenoted PA:PowerAugerFT:FishTailBit HA:HandAugerRB:RockBit DB:DiamondBit=4",N,BBS:BulkSample AS:AugerSamplePM:PressureMeter HS:HollowStemAugerWB:WashBore Standard"N"Penetration:Blowsperfootofa140poundhammerfalling30inchesona2inchO.D.splitspoon,exceptwherenoted. WATERLEVELMEASUREMENTSYMBOLS: WL:WaterLevelWS:WhileSampling WCI:WetCaveinWD:WhileDrilling DCI:DryCaveinBCR:BeforeCasingRemoval AB:AfterBoringACR:AfterCastingRemoval pervioussoils,theindicated Waterlevelsindicatedontheboringlogsarethelevelsmeasuredintheboringsatthetimeindicated.In levelsmayreflectthelocationofgroundwater.Inlowpermeabilitysoils,theaccuratedeterminationofgroundwaterlevelsisnot possiblewithonlyshorttermobservations. DESCRIPTIVESOILCLASSIFICATION PHYSICALPROPERTIESOFBEDROCK SoilClassificationisbasedontheUnifiedSoilClassification DEGREEOFWEATHERING: systemandtheASTMDesignationsD2488.CoarseGrained SlightSlightdecompositionofparentmaterialon Soilshavemovethan50%oftheirdryweightretainedona joints.Maybecolorchange. #200sieve;theyaredescribedas:boulders,cobbles,gravelor ModerateSomedecompositionandcolorchange sand.FineGrainedSoilshavelessthan50%oftheirdryweight throughout. retainedona#200sieve;theyaredescribedas:clays,ifthey areplastic,andsiltsiftheyareslightlyplasticornonplastic. HighRockhighlydecomposed,maybeextremely Majorconstituentsmaybeaddedasmodifiersandminor broken. constituentsmaybeaddedaccordingtotherelative HARDNESSANDDEGREEOFCEMENTATION: proportionsbasedongrainsize.Inadditiontogradation, coarsegrainedsoilsaredefinedonthebasisoftheirrelativein LimestoneandDolomite: placedensityandfinegrainedsoilsonthebasisoftheir HardDifficulttoscratchwithknife. consistency.Example:Leanclaywithsand,tracegravel,stiff ModeratelyCanbescratchedeasilywithknife. (CL);siltysand,tracegravel,mediumdense(SM). HardCannotbescratchedwithfingernail. CONSISTENCYOFFINEGRAINEDSOILS UnconfinedCompressive SoftCanbescratchedwithfingernail. Strength,Qu,psfConsistency Shale,SiltstoneandClaystone: HardCanbescratchedeasilywithknife,cannotbe <500VerySoft scratchedwithfingernail. 5001,000Soft ModeratelyCanbescratchedwithfingernail. 1,0012,000Medium Hard 2,0014,000Stiff 4,0018,000VeryStiff SoftCanbeeasilydentedbutnotmoldedwith fingers. 8,00116,000VeryHard SandstoneandConglomerate: RELATIVEDENSITYOFCOARSEGRAINEDSOILS: WellCapableofscratchingaknifeblade. Cemented NBlows/ftRelativeDensity 03VeryLoose CementedCanbescratchedwithknife. 49Loose PoorlyCanbebrokenaparteasilywithfingers. 1029MediumDense Cemented 3049Dense 5080VeryDense 80+ExtremelyDense EarthEngineeringConsultants,LLC UNIFIED SOIL CLASSIFICATION SYSTEM Soil Classification Group Name Group Symbol Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests Coarse - Grained Soils Gravels more than Clean Gravels Less EF GW CuWell-graded gravel more than 50% 50% of coarse than 5% fines EF GP Cu<4 and/or 1>Cc>3Poorly-graded gravel retained on No. 200 fraction retained on sieveNo. 4 sieve Gravels with Fines G,H Fines classify as ML or MHGM Silty gravel more than 12% F,G,H Fines Classify as CL or CHGC Clayey Gravel fines Sands 50% or more Clean Sands Less EI SW CuWell-graded sand coarse fraction than 5% fines EI SP Cu<6 and/or 1>Cc>3Poorly-graded sand passes No. 4 sieve Sands with Fines G,H,I Fines classify as ML or MHSM Silty sand more than 12% G,H,I Fines classify as CL or CHSC Clayey sand fines Fine-Grained Soils Silts and Clays K,L,M inorganic PI>7 and plots on or above "A" LineCL Lean clay 50% or more passes Liquid Limit less K,L,M PI<4 or plots below "A" LineML Silt the No. 200 sievethan 50 K,L,M,N organic Liquid Limit - oven dried Organic clay <0.75OL K,L,M,O Liquid Limit - not dried Organic silt Silts and Clays K,L,M inorganic PI plots on or above "A" LineCH Fat clay Liquid Limit 50 or K,L,M PI plots below "A" LineMH Elastic Silt more K,L,M,P organic Liquid Limit - oven dried Organic clay <0.75OH K,L,M,O Liquid Limit - not dried Organic silt Primarily organic matter, dark in color, and organic odor Highly organic soilsPTPeat 2 AK (D) E30 Based on the material passing the 3-in. (75-mm) if soil contains 15 to 29% plus No. 200, add "with sand" Cu=D/D Cc= 6010 sieveD x Dor "with gravel", whichever is predominant. 1060 B L If field sample contained cobbles or boulders, or If soil contains both, add "with cobbles or boulders, or both" to add "sandy" to group name. F group name. M If soil contains If soil contains C G add "gravelly" to group name. Gravels with 5 to 12% fines required dual symbols: If fines classify as CL-ML, use dual symbol GC- N PI GW-GM well graded gravel with siltCM, or SC-SM. O H PI GW-GC well-graded gravel with clay If fines are organic, add "with organic fines" to P PI plots on or above "A" line. GP-GM poorly-graded gravel with siltgroup name Q I PI plots below "A" line. GP-GC poorly-graded gravel with clay If soil contains >15% gravel, add "with gravel" to D Sands with 5 to 12% fines require dual symbols:group name J SW-SM well-graded sand with silt If Atterberg limits plots shaded area, soil is a CL- SW-SC well-graded sand with clayML, Silty clay SP-SM poorly graded sand with silt SP-SC poorly graded sand with clay 60 For Classification of fine-grained soils and fine-grained fraction of coarse-grained 50 soils. Equation of "A"-line ) I Horizontal at PI=4 to LL=25.5 40 P ( X then PI-0.73 (LL-20) E D Equation of "U"-line N I Vertical at LL=16 to PI-7, 30 Y T I then PI=0.9 (LL-8) C I T S A L20 P MH OR OH 10 ML OR OL CL-ML 0 0102030405060708090100110 LIQUID LIMIT (LL) Earth Engineering Consultants, LLC Auger Refusal SB-1 thru SB-13:Supplemental BoringsSB-8 & SB-11: PiezometerGroundwater Monitoring LegendDrilled 10-20' and/orPVC Casing Installed forBorings Completed inNovember 2006 (EECProject Number 1062148) EARTH ENGINEERING CONSULTANTS, LLC Approximate Footprint of Recently Razed Building SB-13 Estes Park, Colorado SB-12 Figure 1: Boring Location Diagram Estes Park Community Recreation Center EEC Project Number: 1162032 Date: April 2016 SB-3 SB-6 SB-10 SB-1 SB-4 SB-7 SB-5 SB-2 SB-9 SB-11 SB-8 2 1 Auger Refusal SB-1 thru SB-13:Supplemental BoringsSB-8 & SB-11: PiezometerGroundwater Monitoring LegendDrilled 10-20' and/orPVC Casing Installed forBorings Completed inNovember 2006 (EECProject Number 1062148) Approximate Footprint of Recently Razed Building EARTH ENGINEERING CONSULTANTS, LLC SB-13 SB-12 Estes Park, Colorado SB-3 SB-6 SB-10 Figure 2: Boring Location Diagram SB-1 Estes Park Community Recreation Center SB-4 SB-7 EEC Project Number: 1162032 Date: April 2016 SB-5 SB-2 SB-9 SB-11 SB-8 2 1 Auger Refusal SB-1 thru SB-13:Supplemental BoringsSB-8 & SB-11: PiezometerGroundwater Monitoring LegendDrilled 10-20' and/orPVC Casing Installed for EARTH ENGINEERING CONSULTANTS, LLC Approximate Footprint of Recently Razed Building SB-13 SB-12 Estes Park, Colorado SB-3 Figure 3: Boring Location Diagram Estes Park Community Recreation Center SB-6 SB-10 EEC Project Number: 1162032 Date: April 2016 SB-1 SB-4 SB-7 SB-5 SB-2 SB-9 SB-11 SB-8 2 1 E STES V ALLEY C OMMUNITY C ENTER E STES P ARK,C OLORADO EECP ROJECT N O.1162032 A PRIL 2016 ESTES VALLEY COMMUNITY CENTER ESTES PARK, COLORADO PROJECT NO: 1162032LOG OF BORING B-1DATE:APRIL 2016 SHEET 1 OF 1 RIG TYPE: CME55WATER DEPTH FOREMAN: DGSTART DATE4/8/2016WHILE DRILLINGNone AUGER TYPE: 4" CFA FINISH DATE4/8/2016AFTER DRILLINGN/A SPT HAMMER: AUTOMATICSURFACE ELEV755124 HOURN/A SOIL DESCRIPTION DNQUMCDD-200A-LIMITSSWELL TYPE(FEET)(BLOWS/FT)(PSF)(%)(PCF)LLPI(%)PRESSURE% @ 500 PSF ASPHALT - 3"_ _ 1 DECOMPOSED GRANITE_ _ brown / rust2 _ _ CS33290008.2120.6311221.4<500 psfNone _ _ 4 _ _ SS550--4.2 _ _ 6 more competent with depth_ _ 7 _ _ 8 _ _ 9 _ _ SS1050/2"9000+1.4 _ _ 11 _ _ 12 _ _ 13 _ _ 14 _ _ SS1550/4"--2.5 _ _ BOTTOM OF BORING DEPTH 15.5'16 _ _ 17 _ _ 18 _ _ 19 _ _ 20 _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ 25 _ _ Earth Engineering Consultants, LLC ESTES VALLEY COMMUNITY CENTER ESTES PARK, COLORADO PROJECT NO: 1162032LOG OF BORING B-2APRIL 2016DATE: SHEET 1 OF 1 RIG TYPE: CME55WATER DEPTH FOREMAN: DGSTART DATE4/8/2016WHILE DRILLINGNone AUGER TYPE: 4" CFA FINISH DATE4/8/2016AFTER DRILLINGN/A SPT HAMMER: AUTOMATICSURFACE ELEV754824 HOURN/A SOIL DESCRIPTION DNQUMCDD-200A-LIMITSSWELL TYPE(FEET)(BLOWS/FT)(PSF)(%)(PCF)LLPI(%)PRESSURE% @ 500 PSF ASPHALT - 3"_ _ 1 DECOMPOSED GRANITE_ _ brown / rust2 possible fill_ _ loose above 4'CS31035009.7124.2<500 psfNone _ _ 4 more competent with depth_ _ SS542--3.4 _ _ 6 _ _ 7 _ _ 8 _ _ 9 _ _ CS1050/10"9000+5.0137.4 _ _ 11 _ _ 12 _ _ 13 _ _ 14 _ _ SS1550/3"--3.1 _ _ 16 _ _ 17 _ _ 18 _ _ 19 _ _ SS2050/0.5"--1.1 _ _ BOTTOM OF BORING DEPTH 20.5'21 _ _ 22 _ _ 23 _ _ 24 _ _ 25 _ _ Earth Engineering Consultants, LLC ESTES VALLEY COMMUNITY CENTER ESTES PARK, COLORADO PROJECT NO: 1162032LOG OF BORING B-3APRIL 2016DATE: SHEET 1 OF 1 RIG TYPE: CME55WATER DEPTH FOREMAN: DGSTART DATE4/8/2016WHILE DRILLINGNone AUGER TYPE: 4" CFA FINISH DATE4/8/2016AFTER DRILLINGN/A SPT HAMMER: AUTOMATICSURFACE ELEV755624 HOURN/A SOIL DESCRIPTION DNQUMCDD-200A-LIMITSSWELL TYPE(FEET)(BLOWS/FT)(PSF)(%)(PCF)LLPI(%)PRESSURE% @ 500 PSF ASPHALT - 2.25"_ _ 1 DECOMPOSED GRANITE_ _ brown / grey / rust2 _ _ 3 _ _ 4 _ _ CS550/4"--2.9103.1 _ _ 6 more competent with depth_ _ 7 _ _ 8 _ _ 9 _ _ SS1050/1"--1.6 _ _ 11 _ _ 12 _ _ 13 _ _ 14 _ _ SS15Bounce--1.5 _ _ 16 _ _ 17 _ _ 18 _ _ 19 _ _ SS2050/1"--1.2 _ _ BOTTOM OF BORING DEPTH 20.5'21 _ _ 22 _ _ 23 _ _ 24 _ _ 25 _ _ Earth Engineering Consultants, LLC ESTES VALLEY COMMUNITY CENTER ESTES PARK, COLORADO PROJECT NO: 1162032LOG OF BORING B-4APRIL 2016DATE: SHEET 1 OF 1 RIG TYPE: CME55WATER DEPTH FOREMAN: DGSTART DATE4/8/2016WHILE DRILLINGNone AUGER TYPE: 4" CFA FINISH DATE4/8/2016AFTER DRILLINGN/A SPT HAMMER: AUTOMATICSURFACE ELEV755224 HOURN/A SOIL DESCRIPTION DNQUMCDD-200A-LIMITSSWELL TYPE(FEET)(BLOWS/FT)(PSF)(%)(PCF)LLPI(%)PRESSURE% @ 500 PSF ASPHALT - 3.5"_ _ 1 DECOMPOSED GRANITE_ _ brown / rust2 loose, possible fill near surface_ _ 3 _ _ more competent with depth4 _ _ CS516900011.2124.5<500 psfNone _ _ 6 _ _ 7 _ _ 8 _ _ 9 grey_ _ SS103025004.7 _ _ 11 _ _ 12 _ _ 13 _ _ 14 _ _ SS1550--4.1 _ _ BOTTOM OF BORING DEPTH 15.5'16 _ _ 17 _ _ 18 _ _ 19 _ _ 20 _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ 25 _ _ Earth Engineering Consultants, LLC ESTES VALLEY COMMUNITY CENTER ESTES PARK, COLORADO PROJECT NO: 1162032LOG OF BORING B-5APRIL 2016DATE: SHEET 1 OF 1 RIG TYPE: CME55WATER DEPTH FOREMAN: DGSTART DATE4/8/2016WHILE DRILLINGNone AUGER TYPE: 4" CFA FINISH DATE4/8/2016AFTER DRILLINGN/A SPT HAMMER: AUTOMATICSURFACE ELEV755424 HOURN/A SOIL DESCRIPTION DNQUMCDD-200A-LIMITSSWELL TYPE(FEET)(BLOWS/FT)(PSF)(%)(PCF)LLPI(%)PRESSURE% @ 500 PSF ASPHALT - 3"_ _ 1 DECOMPOSED GRANITE_ _ brown / rust2 _ _ 3 _ _ 4 _ _ CS5485003.3124.9 _ _ 6 more competent with depth_ _ 7 _ _ 8 _ _ 9 _ _ SS1050/9"5006.4 _ _ 11 _ _ 12 _ _ 13 _ _ 14 _ _ SS1550/6"--6.0 _ _ BOTTOM OF BORING DEPTH 15.5'16 _ _ 17 _ _ 18 _ _ 19 _ _ 20 _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ 25 _ _ Earth Engineering Consultants, LLC ESTES VALLEY COMMUNITY CENTER ESTES PARK, COLORADO PROJECT NO: 1162032LOG OF BORING B-6APRIL 2016DATE: SHEET 1 OF 1 RIG TYPE: CME55WATER DEPTH FOREMAN: DGSTART DATE4/8/2016WHILE DRILLINGNone AUGER TYPE: 4" CFA FINISH DATE4/8/2016AFTER DRILLINGN/A SPT HAMMER: AUTOMATICSURFACE ELEV755624 HOURN/A SOIL DESCRIPTION DNQUMCDD-200A-LIMITSSWELL TYPE(FEET)(BLOWS/FT)(PSF)(%)(PCF)LLPI(%)PRESSURE% @ 500 PSF ASPHALT - 3.5"_ _ 1 DECOMPOSED GRANITE_ _ brown / grey / rust2 _ _ 3 _ _ 4 _ _ CS550/6.5"--3.6115.7 _ _ 6 more competent with depth_ _ 7 _ _ 8 _ _ 9 _ _ SS1050/4"--2.5 _ _ 11 _ _ 12 _ _ 13 _ _ 14 _ _ SS1550/2.5"--3.6 _ _ BOTTOM OF BORING DEPTH 15.5'16 _ _ 17 _ _ 18 _ _ 19 _ _ 20 _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ 25 _ _ Earth Engineering Consultants, LLC ESTES VALLEY COMMUNITY CENTER ESTES PARK, COLORADO PROJECT NO: 1162032LOG OF BORING B-7APRIL 2016DATE: SHEET 1 OF 1 RIG TYPE: CME55WATER DEPTH FOREMAN: DGSTART DATE4/8/2016WHILE DRILLING12.5' AUGER TYPE: 4" CFA FINISH DATE4/8/2016AFTER DRILLINGN/A SPT HAMMER: AUTOMATICSURFACE ELEV755824 HOURN/A SOIL DESCRIPTION DNQUMCDD-200A-LIMITSSWELL TYPE(FEET)(BLOWS/FT)(PSF)(%)(PCF)LLPI(%)PRESSURE% @ 500 PSF ASPHALT - 3"_ _ 1 DECOMPSOED GRANITE_ _ brown / grey2 loose, possible fill above 5 to 6'_ _ CS399000+11.0120.1<500 psfNone _ _ 4 _ _ more competent with depthSS511300010.6 _ _ 6 _ _ 7 _ _ 8 _ _ 9 _ _ CS1050/8"9000+5.8142.7 _ _ 11 _ _ 12 _ _ 13 _ _ 14 _ _ SS1550200010.0 _ _ 16 _ _ 17 _ _ 18 _ _ 19 _ _ SS206030007.6 _ _ BOTTOM OF BORING DEPTH 20.5'21 _ _ 22 _ _ 23 _ _ 24 _ _ 25 _ _ Earth Engineering Consultants, LLC ESTES VALLEY COMMUNITY CENTER ESTES PARK, COLORADO PROJECT NO: 1162032LOG OF BORING B-8 (PIEZOMETER)APRIL 2016DATE: SHEET 1 OF 1 RIG TYPE: CME55WATER DEPTH FOREMAN: DGSTART DATE4/8/2016WHILE DRILLING17' AUGER TYPE: 4" CFA FINISH DATE4/8/2016AFTER DRILLING18.8' SPT HAMMER: AUTOMATICSURFACE ELEV75574/15/201612.9 SOIL DESCRIPTION DNQUMCDD-200A-LIMITSSWELL TYPE(FEET)(BLOWS/FT)(PSF)(%)(PCF)LLPI(%)PRESSURE% @ 500 PSF ASPHALT - 3"_ _ BASE - 3"1 _ _ DECOMPOSED GRANITE2 brown / grey_ _ loose, possible fill above 5 to 6'CS310300011.0118.3<500 psfNone _ _ 4 more competent with depth_ _ SS512400017.5 _ _ 6 _ _ 7 _ _ 8 _ _ 9 _ _ CS1050/6"10004.2114.5 _ _ 11 _ _ 12 _ _ 13 _ _ 14 _ _ SS1550/7"--5.7 _ _ 16 _ _ 17 _ _ 18 _ _ 19 _ _ SS2050/6"--8.4 _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ SS25Bounce BOTTOM OF BORING DEPTH 25.5'_ _ Earth Engineering Consultants, LLC ESTES VALLEY COMMUNITY CENTER ESTES PARK, COLORADO PROJECT NO: 1162032LOG OF BORING B-9APRIL 2016DATE: SHEET 1 OF 1 RIG TYPE: CME55WATER DEPTH FOREMAN: DGSTART DATE4/8/2016WHILE DRILLING12' AUGER TYPE: 4" CFA FINISH DATE4/8/2016AFTER DRILLINGN/A SPT HAMMER: AUTOMATICSURFACE ELEV756324 HOURN/A SOIL DESCRIPTION DNQUMCDD-200A-LIMITSSWELL TYPE(FEET)(BLOWS/FT)(PSF)(%)(PCF)LLPI(%)PRESSURE% @ 500 PSF ASPHALT - 3"_ _ 1 DECOMPOSED GRANITE_ _ brown / grey2 _ _ 3 _ _ 4 _ _ CS53760008.7118.7<500 psfNone _ _ more competent with depth6 _ _ 7 _ _ 8 _ _ 9 _ _ SS1050/5"--3.3 _ _ 11 _ _ 12 _ _ 13 _ _ 14 _ _ SS1550/3"--9.3 _ _ BOTTOM OF BORING DEPTH 15.5'16 _ _ 17 _ _ 18 _ _ 19 _ _ 20 _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ 25 _ _ Earth Engineering Consultants, LLC ESTES VALLEY COMMUNITY CENTER ESTES PARK, COLORADO PROJECT NO: 1162032LOG OF BORING B-10APRIL 2016DATE: SHEET 1 OF 1 RIG TYPE: CME55WATER DEPTH FOREMAN: DGSTART DATE4/8/2016WHILE DRILLINGNone AUGER TYPE: 4" CFA FINISH DATE4/8/2016AFTER DRILLINGN/A SPT HAMMER: AUTOMATICSURFACE ELEV756224 HOURN/A SOIL DESCRIPTION DNQUMCDD-200A-LIMITSSWELL TYPE(FEET)(BLOWS/FT)(PSF)(%)(PCF)LLPI(%)PRESSURE% @ 500 PSF ASPHALT_ _ 1 DECOMPOSED GRANITE_ _ brown / grey2 _ _ CS350/7"--3.9106.8 _ _ 4 _ _ with rustSS550/4"--4.1 _ _ 6 more competent with depth_ _ 7 _ _ 8 _ _ 9 _ _ SS1050/7"40006.9 _ _ 11 _ _ 12 _ _ 13 _ _ 14 _ _ SS1550/1"--10.5 _ _ BOTTOM OF BORING DEPTH 15.5'16 _ _ 17 _ _ 18 _ _ 19 _ _ 20 _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ 25 _ _ Earth Engineering Consultants, LLC ESTES VALLEY COMMUNITY CENTER ESTES PARK, COLORADO PROJECT NO: 1162032LOG OF BORING B-11 (PIEZOMETER)APRIL 2016DATE: SHEET 1 OF 1 RIG TYPE: CME55WATER DEPTH FOREMAN: DGSTART DATE4/8/2016WHILE DRILLING12' AUGER TYPE: 4" CFA FINISH DATE4/8/2016AFTER DRILLING11' SPT HAMMER: AUTOMATICSURFACE ELEV75404/15/201610.7' SOIL DESCRIPTION DNQUMCDD-200A-LIMITSSWELL TYPE(FEET)(BLOWS/FT)(PSF)(%)(PCF)LLPI(%)PRESSURE% @ 500 PSF ASPHALT - 3.5"_ _ BASE - 5"1 _ _ DECOMPOSED GRANITE2 brown / grey_ _ 3 _ _ 4 _ _ CS550/10"50003.7139.0 _ _ 6 _ _ 7 _ _ 8 more compentent with depth_ _ 9 _ _ SS1050/6"--6.4 _ _ 11 _ _ 12 _ _ 13 _ _ 14 _ _ SS1550/6"--8.4 _ _ 16 _ _ 17 _ _ 18 _ _ 19 _ _ SS20Bounce _ _ BOTTOM OF BORING DEPTH 20.5'21 _ _ 22 _ _ 23 _ _ 24 _ _ 25 _ _ Earth Engineering Consultants, LLC ESTES VALLEY COMMUNITY CENTER ESTES PARK, COLORADO PROJECT NO: 1162032LOG OF BORING B-12APRIL 2016DATE: SHEET 1 OF 1 RIG TYPE: CME55WATER DEPTH FOREMAN: DGSTART DATE4/8/2016WHILE DRILLINGNone AUGER TYPE: 4" CFA FINISH DATE4/8/2016AFTER DRILLINGN/A SPT HAMMER: AUTOMATICSURFACE ELEV755424 HOURN/A SOIL DESCRIPTION DNQUMCDD-200A-LIMITSSWELL TYPE(FEET)(BLOWS/FT)(PSF)(%)(PCF)LLPI(%)PRESSURE% @ 500 PSF ASPHALT - 3.25"_ _ BASE - 4.75"1 _ _ DECOMPOSED GRANITE2 % @ 150 psf brown / rust_ _ looser near surfaceCS322--6.1111.6500 psf0.5% _ _ 4 _ _ SS517--4.3 more compentent with depth_ _ 6 _ _ 7 _ _ 8 _ _ 9 _ _ SS1050/7"10006.5 _ _ BOTTOM OF BORING DEPTH 10.5'11 _ _ 12 _ _ 13 _ _ 14 _ _ 15 _ _ 16 _ _ 17 _ _ 18 _ _ 19 _ _ 20 _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ 25 _ _ Earth Engineering Consultants, LLC ESTES VALLEY COMMUNITY CENTER ESTES PARK, COLORADO PROJECT NO: 1162032LOG OF BORING B-13APRIL 2016DATE: SHEET 1 OF 1 RIG TYPE: CME55WATER DEPTH FOREMAN: DGSTART DATE4/8/2016WHILE DRILLINGNone AUGER TYPE: 4" CFA FINISH DATE4/8/2016AFTER DRILLINGN/A SPT HAMMER: AUTOMATICSURFACE ELEV756024 HOURN/A SOIL DESCRIPTION DNQUMCDD-200A-LIMITSSWELL TYPE(FEET)(BLOWS/FT)(PSF)(%)(PCF)LLPI(%)PRESSURE% @ 500 PSF GRAVEL - 3"_ _ 1 DECOMPOSED GRANITE_ _ brown / grey2 _ _ CS350/7"20005.1125.5 _ _ 4 _ _ SS550/6"--4.8 _ _ 6 _ _ 7 _ _ 8 _ _ 9 _ _ 10 _ _ 11 _ _ 12 _ _ 13 _ _ 14 _ _ SS1550/6"--4.1 _ _ BOTTOM OF BORING DEPTH 15.5'16 _ _ 17 _ _ 18 _ _ 19 _ _ 20 _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ 25 _ _ Earth Engineering Consultants, LLC SWELL / CONSOLIDATION TEST RESULTS Material Description:Brown / Rust Decomposed Granite Sample Location:Boring 1, Sample 1, Depth 2' Liquid Limit: 31Plasticity Index: 12% Passing #200: 21.4% Beginning Moisture: 8.2%Dry Density: 118.1 pcfEnding Moisture: 12.6% Swell Pressure: <500 psf% Swell @ 500:None 10.0 8.0 6.0 Swell 4.0 2.0 0.0 Percent Movement Water Added -2.0 -4.0 -6.0 Consolidatio -8.0 -10.0 0.010.1110 Load (TSF) Project:Estes Valley Community Center Location:Estes Park, Colorado 1162032 Project #: April 2016 Date: SWELL / CONSOLIDATION TEST RESULTS Material Description:Decomposed Granite Sample Location:Boring 2, Sample 1, Depth 2' Liquid Limit: Plasticity Index: % Passing #200: Beginning Moisture: 9.7%Dry Density: 122.8 pcfEnding Moisture: 12.1% Swell Pressure: <500 psf% Swell @ 500:None 10.0 8.0 6.0 Swell 4.0 2.0 0.0 Percent Movement Water Added -2.0 -4.0 -6.0 Consolidatio -8.0 -10.0 0.010.1110 Load (TSF) Project:Estes Valley Community Center Location:Estes Park, Colorado 1162032 Project #: April 2016 Date: SWELL / CONSOLIDATION TEST RESULTS Material Description:Brown / Rust Decomposed Granite Sample Location:Boring 4, Sample 1, Depth 4' Liquid Limit: 33Plasticity Index: 12% Passing #200: 31.1% Beginning Moisture: 11.2%Dry Density: 124.9 pcfEnding Moisture: 12.2% Swell Pressure: <500 psf% Swell @ 500:None 10.0 8.0 6.0 Swell 4.0 2.0 0.0 Percent Movement Water Added -2.0 -4.0 -6.0 Consolidatio -8.0 -10.0 0.010.1110 Load (TSF) Project:Estes Valley Community Center Location:Estes Park, Colorado 1162032 Project #: April 2016 Date: SWELL / CONSOLIDATION TEST RESULTS Material Description:Decomposed Granite Sample Location:Boring 7, Sample 1, Depth 2' Liquid Limit: 24Plasticity Index: 7% Passing #200: 27.7% Beginning Moisture: 11.0%Dry Density: 115.4 pcfEnding Moisture: 13.5% Swell Pressure: <500 psf% Swell @ 500:None 10.0 8.0 6.0 Swell 4.0 2.0 0.0 Percent Movement Water Added -2.0 -4.0 -6.0 Consolidatio -8.0 -10.0 0.010.1110 Load (TSF) Project:Estes Valley Community Center Location:Estes Park, Colorado 1162032 Project #: April 2016 Date: SWELL / CONSOLIDATION TEST RESULTS Material Description:Decomposed Granite Sample Location:Boring 8, Sample 1, Depth 2' Liquid Limit: Plasticity Index: % Passing #200: Beginning Moisture: 11.0%Dry Density: 118 pcfEnding Moisture: 12.2% Swell Pressure: <500 psf% Swell @ 500:None 10.0 8.0 6.0 Swell 4.0 2.0 0.0 Percent Movement Water Added -2.0 -4.0 -6.0 Consolidatio -8.0 -10.0 0.010.1110 Load (TSF) Project:Estes Valley Community Center Location:Estes Park, Colorado 1162032 Project #: April 2016 Date: SWELL / CONSOLIDATION TEST RESULTS Material Description:Decomposed Granite Sample Location:Boring 9, Sample 1, Depth 2' Liquid Limit: Plasticity Index: % Passing #200: Beginning Moisture: 8.7%Dry Density: 122.9 pcfEnding Moisture: 11.2% Swell Pressure: <500 psf% Swell @ 500:None 10.0 8.0 6.0 Swell 4.0 2.0 0.0 Percent Movement Water Added -2.0 -4.0 -6.0 Consolidatio -8.0 -10.0 0.010.1110 Load (TSF) Project:Estes Valley Community Center Location:Estes Park, Colorado 1162032 Project #: April 2016 Date: SWELL / CONSOLIDATION TEST RESULTS Material Description:Brown / Rust Decomposed Granite Sample Location:Boring 12, Sample 1, Depth 2' Liquid Limit: Plasticity Index: % Passing #200: Beginning Moisture: 6.1%Dry Density: 119.6 pcfEnding Moisture: 14.1% Swell Pressure: 500 psf% Swell @ 150:0.5% 10.0 8.0 6.0 Swell 4.0 2.0 0.0 Water Added Percent Movement -2.0 -4.0 -6.0 Consolidatio -8.0 -10.0 0.010.1110 Load (TSF) Project:Estes Valley Community Center Location:Estes Park, Colorado 1162032 Project #: April 2016 Date: