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HomeMy WebLinkAbout5.0 Sinkhole Geophysical-Geotechnical Investigation 12.02.15p ) 2033 Chenault Drive o Suite 150 o Carrollton, TX 75006 Tel: (972) 713-9109 o Fax: (972) 713-9171 www.geoneenng.com December 2,2005 Mr. David A" Joseph c/o Broadmoor Development I LakeAvenue, Golorado Springs co 80906 Re: Sinkhole GeophysicallGeotechnical lnvestigation Recreation Center Area, & lots 297 - 316 Phase I Block 4 The lronbridge Golf Club and Community 410 lronbridge Drive Glenwood Springs,co 81601 BCI Project No: 05-277 Dear Sir, Attached are our results for the above referenced project, in accordance with your authorization. lt has been a pleasure to perform this work for you, and we appreciate the opportunity to be of service. lf during the course of this project we can be of further assistance, please do not hesitate to contact us. Sincerely, BRYANT GONSULTANTS, INC. -)*1"^ lk -/ Derek V. Morris, Ph.D., P.E. Senior Gonsultant ichael D.'Gehr Project Engineer x"%'q Sean P. Sweeneyr/ Vice-President Geotechnical . ,tm Geo-Structural . Engi neers Prdect Geophysicist Geological & Scientists . Forensic . Materials GEOPHYSICAU G EOTECH N ICAL EXPLORATION for THE RECREATION CENTER AREA, & LOTS 297 - 316 PHASE I BLOCK 4 The lronbridge Golf Glub and Gommunity 410 lronbridge Drive, Glenwood Springs GO 81 601 Reportto: Mr. David A. Joseph c/o LB Rose Ranch, LLP 1007 West Bank RD, Glenwood Springs co 81601 Report by: BRYANT CONSULTANTS, ING. GEOTECHNICAL AND FORENSIC ENGINEERING CONSULTANTS CARROLLTON DALLAS, TEXAS BC! PROJECT NO. 05-277 DEGEMBER 2, 2OO5 TABLE OF CONTENTS PROJECT INFORMATION SCOPE OF INVESTIGATION GENERAL SUBSURFACE CONDITIONS SITE OBSERVATIONS ELECTRICAL RESISTIVITY PROFILI NG GROUND PENETMTING MDAR MICRO-GRAVITY SURVEY GEOTECHNICAL DRILLING ZONE R1 - R2 ZONE R3 ZONE R4 - R5 ZONE R8A ZONE R9 ZONE R1O FINDINGS LIMITATIONS UST OF FIGURES LOCATION PLAN LOCAL TOPOGMPHY AREA ROCK GEOLOGY AREA SOILS GEOLOGY RESISTIVITY INVESTIGATION PLAN, REC. CENTER & LOTS 297-316 1 2 3 8I 14 15 16 18 23 26 29 32 35 38 40 1 2 3 4 5 6 7II 10 11 12 13 14 15 ZONE R1 - R2 ZONE R1 - R2 ZONE R1 - R2 ZONE R1 . R2 ZONE R1 - R2 ZONE R1 _ R2 ZONE R1 - R2 ZONE R1 - R2 ZONE R1 - R2 ZONE R1 - R2 INVESTIGATION PLAN ]NVERTED RES]STIVITY VOLUME STATIC VERTICAL SLICES ISOVOLUME > lOOO OHM.M RADAR ANOMALY UNDER BOREHOLE 83 GRAVITY LINE G1 GRAVITY LINE G2 BORING A1 BORING 81 BORING 83 ZONE R3 ZONE R3 ZONE R3 ZONE R3 ZONE R3 ZONE R3 ZONE R3 ZONE R3 ZONE R4 - R5 ZONE R4 - R5 ZONE R4 - R5 ZONE R4 - R5 ZONE R4 - R5 ZONE R4 - R5 ZONE R4 - R5 ZONE R4 - R5 ZONE R8A ZONE R8A ZONE R8A ZONE R8A ZONE R8A ZONE R8A ZONE R8A ZONE R8A ZONE R8A ZONE R9 ZONE R9 ZONE R9 ZONE R9 ZONE R9 ZONE R9 ZONE R9 ZONE R9 ZONE R9 ZONE R1 O ZONE R1O ZONE R1O ZONE R1O ZONE R1O ZONE R1O ZONE R1O ZONE R1O INVESTIGATION PLAN INVERTED RESISTIVITY VOLUME STATIC VERTICAL SLICES ISOVOLUME > lOOO OHM.M RADAR ANOMALY UNDER BOREHOLE A3 GMVITY LINE G3 BORING 43 BORING 812 INVESTIGATION PLAN I NVERTED RESISTIVITY VOLUME STATIC VERTICAL SLICES ISOVOLUME > 3OOO OHM.M GRAVITY LINE G5 GRAVIry LINE G6 BORING 81O BORING 811 INVESTIGATION PLAN I NVERTED RESISTIVITY VOLUME STATIC VERTICAL SLICES ISOVOLUME > lOOO OHM.M RADAR ANOMALIES UNDER BOREHOLES 86 &7 BORING 86 BORING 87 BORING 88 BORING 89 INVESTIGATION PLAN I NVERTED RESISTIVITY VOLUME STATIC VERTICAL SLICES ISOVOLUME > lOOO OHM.M RADAR ANOMALY UNDER BOREHOLE 84 GRAVITY LINE G4 BORING A2 BORING 82 BORING 84 INVESTIGATION PLAN INVERTED RESISTIVITY VOLUME STATIC VERTICAL SLICES ISOVOLUME > lOOO OHM.M ISOVOLUME > 3OOO OHM.M GRAVITY LINE G7 BORING 85 BORING 813 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33u 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53il 55 56 57 GEOTECHNICAUGEOPHYSICAL INVESTIGATION for RECREATION GENTER AREA, & LOTS 297 - 316 PHASE I BLOCK 4 THE TRONBRIDGE GOLF CLUB AND COMMUNITY 410 IRONBRIDGE DRIVE, GLENWOOD SPRINGS co 81601 PROJECT INFORMATION Based upon authorization by Mr. David Joseph of the lronbridge Golf Club and Community, Bryant Consultants, lnc. (BCl) has completed six three-dimensional geo- electrical inversion blocks, a series of ground- penetrating radar runs, selected gravimetric surveys, and several air-rotary drill holes, at the site of the proposed new recreation center and also in the adjacent Phase 1 Block 4 area (comprising lots 297 - 316) for the lronbridge Golf Club and Community, at 410 lronbridge Drive in Glenwood Springs, Colorado. The overatl location of the project is in Garfield County, Colorado, about seven miles south of Glenwood Springs, and the site of the development area is shown in Figure 1, reproduced adjacently to a smaller scale: BCI reviewed the following information in the preparation of this report: 1. U.S. Dept. of the lnterior, Geological Survey, Geological Map of Colorado. 2. U.S. Dept. of the lnterior, Geological Survey, Cattle Creek Quadrangle,T.S minute series maps. 3. USDA Natural Resource Conservation Service's Soil Survey data for Garfield County (Aspen-Gypsum area), Colorado. 4. Colorado Geologic Survey, Department of Natural Resources, geologic mapping website. 5. Review of Hepworth-Pawlak Geotechnical lnc. reports dated May 31 ,2005, June 30, June 30 again, and July 8, 2005. 6. General experience and knowledge of subsurface conditions and geology. lronbridge Golf Club & Community Page 2 SCOPE OF INVESTIGATION Our scope of investigation for this project was based on the request from Mr. David A. Joseph and Mr. Aaron Bevington. The results of the test program and analysis of findings are presented in this report. Other engineering analyses and recommendations were not within the scope of our investigation at present. This report expressly disclaims providing engineering analysis for foundation design parameters, including analysis for altowable bearing pressures and/or prediction of moisture induced settlement or heave of the soils at this site. The purpose of this investigation was to perform 3-D geo-electrical profiles, ground penetrating radar surveys, and confirmatory geotechnical drill holes, as appropriate at this site. !n some cases, it was also possible to obtain some pertinent engineering properties of the subsurface soils, and to provide general comments on the subsurface and geologic conditions and likety properties. However the objective was to provide geotechnical and geophysical information to assist the lronbridge Golf Club and Community in evaluating the possibility of subsurface sinkholes in the areas in question. A generic location diagram of the boundaries of the development area, overlain on a U.S. Geological Survey topographic map of the area, is shown on the adjacent figure. During earlier phases of development, a couPIe of surface sinkholes opened up while developing the land-use of the area - namely a small one on the North-West edge of the 16th hole fairway, and a larger one at the south end of the cart storage tent that reportedly took some golf carts with it. A borehole drilled just south of the cart storage tent (2124) also hit voids. Also one of general geotechnical boreholes drilled on the site (namely lot 141) encountered voids, although this eventually took a relatively minor amount of grout. BCI Project 0*277 lronbridge Golf Club & Community Page 3 It is known that the area is susceptible to cavity and sinkhole formation, partly because geologically the area was at one time on the shores of a historic lake, along the sides of which gypsum was deposited as the lake dried up. This is a mineral that can be dissolved by water, giving rise to the possibility of solution cavities as the geo- morphological regime changed. GENERAL SUBSURFACE CONDITIONS A considerable amount of prior generic geologic information is available for this location, based on published and publicly available data. Additional site-specific information is also available in the boring log information previously obtained by Hepworth-Pawlak Geotechnical engineers, and presented separately. A summary of the known soil and rock stratigraphy and geology in the area, is given as follows. Geologic Setting The development is located on the west bank of the Roaring Fork river in Garfield County, about six miles south of Glenwood Springs. Previous work by Hepworth-Pawlak Geotechnical has established the presence of significant strata of Eagle Valley Evaporite, which contains dry gypsum mixed in with siltstone and sandstone. Most notably this formation may be prone to subsidence, sink holes, compaction, settlement, piping, and diapiric swelling where evaporitic rocks lie near land surface. The Eagle Valley Evaporite is geologically a sequence of evaporitic rocks consisting mainly of massive to laminated gypsum, anhydrite, and halite, interbedded with light- colored mudstone and fine-grained sandstone, thin carbonate beds, and black shale. lt was primarily deposited in an evaporitic basin formed as the outlet for the sea within the Paleozoic Eagle Basin was restricted. Most clastic sediments in formation likely resulted from transgressive and regressive fluvial and lacustrine deposition. The thickness is reported as highly variable, but averages about 2,000 ft. and varies due to flowage and diapiric activity. Beds commonly are intensely folded, faulted, and ductily deformed by diapirism, flowage, load metamorphism, dissolution, hydration of anhydrite, and regional tectonism, and it may diapirically intrude older colluvium locally. Eagle Valley Evaporite contains voids and caverns that have resulted from near-surface dissolution of evaporite rocks and is prone to development of sinkholes into which overlying surficial deposits may be piped. BCI Project 05-277 lronbridge Golf Club & Community Page 4 According to the Geologic Map of Colorado (a detail from which is reproduced below, reproduced at larger scale in Figure 3 - Area Rock Geology, in the figures following this report), and local experience with the geologic formations in this area, the immediate subsurface conditions consist of unconsolidated surficial deposits and rock of quaternary age, denoted Qg. These will be gravels and alluvium of the Pinedale and Bull Lake age, laid down by the Roaring Fork river, and will include Broadway and Louvier Alluviums from the Pleistocene. The immediately adjacent rock types are sedimentary rocks of the Pennsylvanian age, most notably the Maroon formation (denoted PlPm) consisting of arkosic sandstone, siltstone, conglomerate and local limestone, as well as adjacent Weber sandstone denoted PlPwm. However the development arca itself is shown as being located primarily over Evaporitic Facies (lPee), described as gypsum, siltstone and shale, with salt present in deep borings. lt is noted to inter-tongue with the Lower Maroon (PlPm) and Minturn (lPmb) formations. The Upper and Lower Maroon formations (PlPm) consist of mainly red beds of sandstone, conglomerate, mudstone, siltstone, and claystone with minor, thin beds of gray limestone. Conglomerate contains pebble- and cobble-sized clasts. lt is commonly arkosic and very micaceous. The Weber Sandstone member ( PlPwm) consists of light gray to greenish black, grayish red, and pale reddish brown, fine-grained, feldspathic sandstone and conglomeratic sandstone which contains locally abundant interstitial and grain-coatings of solid hydrocarbon. Nodules of pyrite occasionally present in middle of Weber Sandstone Member. Total thickness about 3,OOO to 4,000 ft, including the 150- to 175- BCI Project 05-277 lronbridge Golf Club & Community Page 5 ftthick Weber Sandstone Member. Generally poorly exposed in quadrangle. Deposition probably occurred in braided streams and on adjoining flood plains and distal sheet- wash areas in a large, coalescing alluvial fan complex on the margin of the Eagle Basin in an arid or semLard climate. Geologic Hazards ln the state of Colorado, the nature of a geologic hazard has now actually been defined by the legislature. Cotorado House Bill 1041 states that a geologic hazard is ' a geologic phenomenon which is so adverse to past, current, or foreseeable construction or land use as to constitute a significant hazard to public health and safety or to property". It has been noted (Lovekin, J.R., & Higgins, J.D., 2003, "Major Geologic Hazards Along the Roaring Fork River near Glenwood Springs, Colorado", Colorado Geological Survey Special Publication 55 "Engineering geology in Colorado") that there are numerous potential geologic hazards in the Highway 82 corridor. Most can be associated with one of three scenarios: (a) interaction of water and evaporate bedrock (b) interaction of water with weathered bedrock and colluvium on steep slopes, or (c) interaction of water with surficial materials that have a loose soil structure or contain significant quantities of soluble minerals. Since this is a semi-arid region, the natural processes tend to be very slow to progress, and the frequency of damage is relatively low. However, recent development in the area is typically adding significant volumes of water to the ground through irrigation systems and concentration of storm water runoff from buildings and flatwork. Based on observations of problems associated with past practices, the new development is likely to result in a much higher than normal frequency of damage to engineered structures unless mitigation measures are put in place. Soil Stratigraphy Based upon the USDA Soil Conservation Service, Soi! Survey of the Aspen-Gypsum Area (May 1992), this site is situated predominantly on Almy loam soil, but with the Uracca-Mergel complex closer to the road. There are also some terraces of Redrob loam bordering on the river in places. The following figure also shows the original distribution of surface soils in the area, as mapped by the Soil Conservation Service. A larger version of this figure is shown as Figure 4 - Area Sor/s Geology, at the end of this report. BCI Project 05-277 lronbridge Golf Club & CommunitY Page 6 The original intention of these maps was to assist in the use and management of large areas, and contains predictions of soil behavior for selected land uses. The survey is also intended to highlight limitations and hazards inherent in the soil, improvements need to overcome the limitations, and the impact of selected land uses on the environments. Use of the general county soil survey is a reasonable means of identifying generat soit properties and conditions at a site prior to site-specific geotechnical information. This site is situated primarily on the Almy loam, which is denoted as soil type 6 on the USDA Soil Survey map. This a deep well drained soil on fans and uplands, and is formed in alluvium derived dominantly from calcareous redbed sandstone and shale, at elevations of 6,000 to 7,800 feet. The surface layer is usually described as reddish brown loam about 8 inches thick, with the upper 3" of the subsoil fine sandy !oam, and the lower 15" sandy clay loam. The soil is described as calcareous to a depth of 1 1 inches, and calcareous below that depth. Permeability is moderate in the Almy soil, available water capacity is high, runoff is medium, and the hazard of erosion moderate. BCI Project 05-277 lronbridge Golf Club & CommunitY Page 7 The upper portions of the site are mapped as being on the Uracca-Mergel soil complex, with 12to 25o/o slopes, extremely stony, on alluvial fans and valley side slopes (soil type 109 on the published map). lncluded in this area are small areas of soils that are similar to the Uracca and Mergel soils, but with a thicker surface area and a lower content of coarse fragments. The Uracca soil is described as deep and we!!-drained, forming in alluvium derived dominantly from mixed igneous and metamorphic material. About 3 to 15% of the surface is covered with boulders, stones, cobbles and gravel. Typically the surface layer is brown cobbly sandy loam about 2 inches thick; the upper 4' of the subsoi! is cobbly sandy loam; the lower 6" is very cobbly sandy clay loam; and the substratum to a depth of 60" or more is extremely cobbly loamy sand. The content of coarse fragments ranges from 35 to 85%. Permeability is moderately rapid, available water capacity is !ow, runoff is medium, and the hazard of water erosion is slight or moderate. The Mergel soit is atso deep and well-drained, but formed in glacial outwash. About 3 to 30 % of the surface is covered with boutders, stones, cobbles and gravel. Typically the surface layer is grayish brown cobbly loam about 7" thick. The upper 11" of the substratum is very cobbly sandy loam. The lower part to a depth of 60" is extremely stony sandy loam. The content of coarse fragments ranges from 355 to 80%. Permeability in the Mergel soil is moderate, and available water capacity is low. Runoff is slow, and the hazard of erosion is slight. ln addition, there are some terraces of Redrob loam close to the river (denoted as soil type 92 on the maps). This deep somewhat poorly drained soil is on alluvial valley floors, Iow terraces, and flood plains, and formed in mixed alluvium derived predominantly from sandstone and shale. Typically the surface layer is dark grayish brown loam about 14" thick. The next layer is stratified stony loam about 6" thick, while the substratum to a depth of 60" is stony and very cobbly loamy sand. Permeability is moderate in the surface layer of the Redrob soil, and rapid in the rest of the profile. Available water capacity is low; runoff is slow, and the hazard of erosion is slight or moderate on the steeper slopes. Based upon site observations and the available drilling information, BCI is of the opinion that observed soi! conditions are similar to those identified in the published geologic and soil sources mentioned above. BCI Project 05-277 lronbridge Golf Club & Community SITE OBSERVATIONS The adjacent figure shows the general position of the investigation in question, which was caried out during late September 2005, approximately at the site of the planned Recreational Center, and also at what was understood to be lots 297 to 316 comprising Phase 1 Block 4 of the lronbridge Development. This was also the area where a recent large sinkhole of depth and diameter 50 feet or so, had been observed earlier in the year in the area just to the south of the present golf cart storage tent (just to the west of the location for the proposed Recreational Center). We understand that this area had collapsed without warning, and was subsequently filled in with select fill followed by grout. ln order to establish the more precise positions of the grid investigated, the positions were recorded in the field by a high- precision Global Positioning System, in addition to staking out in the field. These could be overlaid on detailed CAD drawings of the development plan details at the site, as is shown on later figures. GeneralArcm # .? .*l F,:."F Investigated in thb Phasr of Invetigation BCI Project 05-277 lronbridge Golf Club & Communi$Page 9 ELECTRICAL RESISTIVITY PROFILING Layout and Field Measurements The primary tool of investigation employed at this site, was multi-electrode inverse resistivity testing. There are a number of geometries that can be used for set-out of the electrodes, and for subsequent analysis, but on this project three-dimensional arays were mostly employed, since BCI's experience has been that two-dimensional resistivity testing is normally inadequate to pick up voids, unless they are close to the center-line of the ar,ay. This pQect used 3-D Geo-Electrical Moisture/Material lmaging Resistivity (GMMIR) profiles on the appropriate lots, at an overall spacing of about 300 feet by around 100 feet per three-dimensional anay. The precise dimensions of the actual anay was finalized in the field, but the use of a large array like this, firstly gave a substantial depth of penetration into the subsurface of around 70 feet, and secondly permitted the collection of a larger data set within a given period of time. The relative electrode spacings in the X and Y directions could also be varied, and were optimized in the field depending on the lot layouts in the appropriate locality. The surface outlines of the blocks investigated in this phase of the testing, are shown adjacent (and are reproduced in more detail in the main figures as Figure 5 - Reststivity Location Plan for this Phase). Electrical resistivity methods do not directty provide information regarding the density of the soil materials, but provide information regarding the moisture and materia! differences and resistivity contrasts at a site with depth. The resolution of etectrical resistivity methods decreases with depth but in the upper 100 feet, resolution has been found to be good. ln this case, the purpose of the profiling was to evaluate various causes associated with the variation of the subsurface materials encountered at this site, which has been found to include sub-surface voids, which normally show up as an ultra-high resistivity zone. BCI Project 05-277 lronbridge Golf Club & Community Page 10 As indicated, in order to estabtish possible voids and/or weak zones in the subsurface in the zone in question, 3-D geo-electrical multi-electrode resistivity profiles were performed on site. This involved laying out electrodes in a circuitous layout, starting at an origin, and then proceeding upwards at an electrode spacing that was usually about 3 to 4 m. (about 10 ft.). The line was then continued back down at a lateral spacing from the first line, and then back up again after moving across another lateral spacing etc. tn this way, the electrode configuration covered the block in question in a series of multiple S-shaped loops, and the adjacent figure shows typical color resistivity contours converted into a block geometry, and with co-ordinates shown on the side of the block in meters. Measurements of the field resistivity were performed in general accordance with ASTM G-57 with modifications of the electrode configuration. The actual position of the corner electrodes was determined by global positioning in the -0.0 -7 -O Z -1.+.0 -21.0n 9s_9 field, using a hand-held differential global positioning receiver, so that the outline of each block could then be plotted accurately on Figure 5 - Resistivity Location Plan. Geoelectrical lmaging Assumptions and Gomputer Data Modeling Three-dimensiona! computer inversions were performed using a least-squares approximation to provide the "best fit" between the apparent resistivity field data and the assumed computer resistivity structure model. Three-dimensional subsurface objects are assumed in the inversion process which implies that the resistivity structure modeled is parallel to each profile and integrates the effects perpendicular to the profile. Methods used to analyze and collect the field data, as well as interpretation of these geo-electrical moisture/material imaging resistivity (GMMIR) profiles are based upon a patented process, US Patent S/N 6,295,512, all rights reserved. Resistivity profiling is used throughout the mining, engineering and environmental fields to evaluate the moisture and material properties of soil and rock materials, for geologic and other purposes. The electrical resistivity scales used were truncated at around 5000 ohm-m to provide a uniform scale of resistivity values for comparison purposes. Actual resistivity values of the materials in the red areas may be slightly greater than BCI Project 05-277 0.0 0.0 lronbridge Golf Club & CommunitY Page 11 50OO ohm-m in places, although at this location this value appeared to be a realistic maximum for the site, and it is fairly rare for soils to show resistivities greater than this. !n addition to plotting the results as a block diagram (which could be viewed from a variety of different angles if desired, such Z as from underneath), the software also allowed the results to be manipulated in a number of ways. This included viewing the resistivity values as a series of slices (which could be horizontal as well as vertical), as shown in the adjacent example. The advantage of this is that it allowed imaging of the electrical structure 0.00.0 6-0 x rather than just on the outside to portray a solid diagram of An example of this is shown the block, that have a resistivity -0.0 -7 -O -14.0 -2L.0 9s.9 129 18.0 within the body of the scanned block to take place, surfaces of the surveyed block. As an additiona! variation, a further possibility was resistivity values above a certain limiting resistivity. adjacent, which shows the outlines of the areas within in excess of 1000 ohm.m (in this case). This was found to be a useful way of portraying high-resistivity anomalies in a rapid and visuatly understandable fashion, z so that further work could then be planned over the areas of interest, and drill-holes (for instance) located over these spots. ln some cases, a threshold resistivity of 3000 ohm.m was used as well, in order to highlight potentially anomalous areas. -218.6 o-o o-o Analysis of Contours The nature of the data inversion from the field multi-electrode resistivity measurements, is such that the inversion data is most easily portrayed graphically as a series of color contours, for ease of overalt interpretation and integration into the overall geologic interpretation. As shown on the accompanying figures, the color scales used in the BCI Project 05-277 -o-o -7 -O 6.0v lZO 18-O lronbridge Golf Club & Community Page 12 profiles, can range from dark blue to bright red. The dark blue colors represent the lowest resistivity values encountered on the order of 15 ohm-m or less, while the bright red and brown colors represent the highest measured values of over 3000 ohm-m. For discussion purposes (and in order to correlate with the properties of various forrirations), the terminology used here regarding the classification of the color scale shown, can be summarized as follows: very high high moderately high moderate moderately low low very low 5000.oo 4000.oo 3000.oo 2000.oo 1500.oo 1000.oo 750.OO 500.oo 350.OO 225.OO 150.OO 10 0.oo 75.OO 60.oo 45.OO 30.oo 20.oo 15 .OO 10 .oo 7-50 5. OO 4000 to >5000 ohm.m 2000 to 4000 ohm.m: 1000 to 2000 ohm.m; 50S tr: t00C chm.rn: 75 to 500 ohm.m: 30 to 75 ohm.m:<5 to 30 ohm.m: As can be seen from the graphical plots produced, resistivity values of less than about 30 ohm.m (darker blues) were essentially not observed at this location. Some areas of lighter btue mate[ial were detected, associated probably with some wetter areas as will be discussed shortly, but most of the formation was portrayed as predominantly green in color, corresponding to resistivity values of a few hundred ohm.m., (as might be expected for this location where the upper material was predominantly dry). Within the predominantly green values, there were some regions of :rell*'u,r and orange (corresponding to more resistive zones - probably dry soil and/or sands and gravels). ln addition, there were the occasional pockets of red and brown material, which could either be rock boulders, very dry coarse soil, or possible voids (which in theory correlate to an infinite resistance). These regions are therefore the suspicious regions as far as this investigation is concerned. The following paragraphs summarize the usual relationship between these resistivity values (and the subsequent colors) and the normal respective geologic strata. Ultra-tow resistivity values < 5 ohm-m are usually indicative of wet to very wet clayey soils with associated groundwater. These would be shown as very dark indigo on this scale, and were essentially not detected at this site. Resistivity values described here as very low (5 to 30 ohm+n) would be very dark blue on this scale, and typically indicate plastic clays with moisture contents above their plastic limits. Again these were basically not detected at this site. BCI Project 05-277 lronbridge Golf Club & Community Page 13 Low (30 to 75 ohm.m) resistivity values are represented by lighter blue on this chart, and were detected in a number of places on the cross-sections. Based on usual geotechnical information, such values are typically indicative of comparatively drier clays and silts - i.e. fine-grained soils with moisture contents at or below their corresponding plastic limits. Pockets of such material occurred here, although most of the stratum was of higher resistivity than this, indicating that most of it was of coarser consistency, as might be expected from the boreholes previously drilled by HP Geotech. Moderately low resistivity values (75 to 500 ohm.m) are represented by various shades of green on this chart, and were the predominant values measured in the field exploration. Based on usual geotechnical information, such values are usually indicative of sandy silts and silty sands, which correlates to the results of traditional drilling previously observed. Mselerate and moderately high resistivity values on the order of 5*0 to 2000 ohm-m are represented by the yellaw/orange cotors here, and are typically indicative of dry sands and gravels. Substantial zones of such materia! was detected here, especially close to the surface in some areas. High resistivity values on the order of 2000 to 4000 ohm-m are shown in red, and are usually indicative of very coarse material, such as gravels. Some intact rocks also fall into this category, if for instance they were boulders within the soil cross-section. Some of this materia! was detected here. Likewise very high resistivity values (4000 to 5000 + ohm.m) would either be non- conducting pockets of very dry grave!, massive rocks, or possible air voids as discussed below, and would be displayed here as brown in color. Most importantly for this investigation, any voids in the cross-section would also be expected to display very high resistivity values (over 4000 ohm.m., as a void is essentially non-conducting), and (if present) should be indicated in this region. BCI Project 05-277 lronbridge Golf Club & Community Page 14 GROUND PENETRATING RADAR Ground penetrating radar (GPR) is a non-destructive technique that emits a short pulse of electromagnetic energy into the subsurface. When this pulse strikes an interface between layers of materials with different electrical properties, part of the wave reflects back, and the remaining energy continues to the next interface. GPR evaluates the reflection of electromagnetic waves at the interface between two different dielectric materials. The penetration of the waves into the subsurface is a function of the media dielectric constants. A GSSI SIR 10B control system was used with a 100 megaHertz (MHz) monostatic antenna to evaluate the subsurface conditions at this site. A 100 MHz antenna was utilized to provide a medium- resolution picture at deeper depths. (Higher frequency antennae provide higher-resolution pictures but with limited penetration depths - a 400 MHz antenna might be typically used to locate buried utilities, drums, concrete pipes and storage tanks close to the surface, while a 100 MHz antenna is typically used to locate larger scale geologic features). The use of GPR potentially supplements the geo-electrical investigation, as it is in principle better in detecting anomalies close to the surface, especially if a long-wavelength (low frequency) antenna is used. Signal penetration depths are also a function of soil type. Typically, a clayey type soil attenuates the pulse signal, which tends to be the major limitation of this technique in fine-grained soil conditions. Better soil conditions for GPR include dry, granular type soils such as sands and/or gravels, and this is likely to be predominantly the case at this site. Based upon current 100 MHz antenna configuration, the maximum signal penetration depths observed at this site were approximately 15 to 20 feet below grade in most instances. BCI Project 05-277 lronbridge Golf Club & Community Page 15 MIGRO.GRAVITY SURVEY it has also been found that micro-gravity surveys are a good fundamental way of detecting voids in the ground (modern equipment permitting measurement to one part per billion of the earth's gravitational field). This is because any change in density in the subsoil will result in a microscopic change in the local gravitation field, and obviously the largest density deficit occurs when one has a void in the subsurface. Gravimetric surveys were only performed on those locations that appeared to display anomalous properties, depending on the results of the previous surveys. This was therefore not intended to be a major component of the project, but was mainly useful in providing additional information. The instrument used was a LaCoste & Romberg model G gravity meter, leased from LaCoste & Romberg in Austin, TX, a photo of which is shown adjacent. This is field portable device, which is a relative gravity meter - i.e. it is designed primarily to measure the difference in gravity between two observation locations - and has a sensitivity of around 0.01 milliGal (i.e. 10 -8 of earth's gravity, since a Gal is defined as an acceleration of 1 cm/s). The instrument is made out of metal and therefore must be maintained at a constant temperature to avoid thermal expansion and contraction, maintained by an internal battery-driven heater. !t basically uses a mass on the end of a spring that stretches where g is stronger, and can measure g with a precision of 0.01 mGal in about 5 minutes. As well as voids, various rock types within a study area often contrast enough in density to cause gravity anomalies - for example, sedimentary rocks that fill basins almost always have low densities and are characterized by gravity lows on anomaly maps, while mafic rocks, which contain high-density minerals, often are associated with gravity highs. The changes of gravity from one point to another, enables the calculation of an average density, and is often used in exploration for oil and gas. For this application it is superior to backscatter density logs because it is sensitive to sub-surface density some distance away. BCI Prcject 05-277 lronbridge Golf Club & Community Page 16 GEOTECHNICAL DRILLING Confirmatory geotechnical drilling was carried out at certain locations, notably those where an anomaly was noted, and where the possibility of a void was thought to be significant. This drilling was performed without intact recovery of soil or rock samples (i.e. without thin-walled soil sampling tubes, or rock corers), for increased speed and efficiency, as it was not considered necessary to recover intact samples in this instance. However disturbed samples of the subsoil were recovered at intermittent intervals, which could be classified visually, and on which soil classification tests could be performed. This enabled brief logs of the drill holes to be prepared - initially recorded by hand at the site, but then modified in the BCI laboratories after inspection, as appropriate. Preliminary drilling was attempted for reasons of economy initially with a conventional truck-mounted auger drill, but at this site penetration rates were very limited with this method. Three holes were attempted in this way, and these were labeled A-1, A-2 & A- 3, and are included in the appropriate logs of borings. However the maximum depth achieved was only 16 feet. Consequently an ODEX rotary percussion system was subsequently employed, which is suitable for adverse unconsolidated or rock formations, where techniques such as conventional mud rotary or augering fail. This method uses a percussion hammer combined with a rotary under- reaming feature, to install casing through difficult layers that are encountered after initial penetration. The ODEX annulus is slightly larger than the casing, so that the casing can be advanced with greatly reduced downforce. The drill system and high-capacity air compressor was provided by Ager Drilling of Yampa, CO - a photo of the field system is shown adjacent. BCI Project 05-277 lronbridge Golf Club & Community Page 17 The drill hole tocations were located in the field by BCI personnel, based on the data previously obtained from the geophysical work. Rough field logs were prepared in the field for the exploratory holes made on this project, and bag samples of soil cuttings were then retained and shipped back by Federal Express courier to the BCI laboratories, for the preparation of the final logs of borings. These were the most retiable drilling logs at this site, and for this phase were labeled B-1 through B-13. The biggest difficulty in practice was in penetrating the very coarse gravels and boutders underlying much of the site - as might be expected from the alluvial and fluvial characteristics of the transported material on either side of the Roaring Fork River. Otherwise site access and accessibility (in good weather) was generally good, with a generic photo of the terrain shown adjacent (looking South from the present pro shop). The samples taken by this drilling method consisted of disturbed soil samples, which were not suitable for intact strength testing, but this was not the issue in this case, since the main purpose of drilling was to carry out a physical check to see that no voids were present at a particular location. Nevertheless, some moisture content and resistivity measurements were carried out on some of the bag samples, (mostly obtained from the cuttings or chippings entrained in the exhaust stream from the air rotary drilling process) out of interest, although the moisture content values cannot be assumed to be identical to the values in the ground, since the process of drilling with air will tend to dry out soil cuttings. The recorded moisture contents will therefore be a lower bound to the in-situ values, but nevertheless were an indication of relative wetness in the sub-strata. BCI Project 05-277 lronbridge Golf Club & Communrty ZONE R1 - R2 Electrica! Resistivity Profi li ng As part of the process of investigating the subterranean conditions at the site, BCI conducted a three-dimensional "roll-along" survey over the area described in Figure 5 as Zone Rl - R2, and highlighted in on the adjacent graphic. The position of the origin for the X and Y co-ordinates used to describe the position of any measurement or slices or anomalies etc is also shown at the lower left @rner of the rectangular surface projection of the The results of the back-analylzed sections produced in this area are shown in detail in Figures 7 through 9 at the end of this report, together with the color scale used in the contouring system, as discussed previously. However it can be seen from the main figures that the block diagram presentation did not show any obviously high-resistivity zones in the -ESo standard view (at least around the perimeters of -7-o the block). Since such a presentation only shows z -I.l values on the surface of the rectangular figure portrayed, the presentation as a series of slices was also studied, and the ful!-scale results are shown in Figure 8 of the main figures. As can be seen from the adjacent smaller-scale images, a more concentrated higher- resistivity *hot-spot" was noted within the body of the block, at approximately co-ordinates X = 15, Y = 65. This can be seen clearly on both views of the slices in the block - i.e. looking Northwards from underneath initially, followed by a view Southwards from above. scanned area. -0.0 '7 -O z -14.0 L?-o 24.9 x BCI Project 05-277 '2Lt lronbridge Golf Club & Community Page 19 The significance of the colors and the resistivity values has already been discussed, and in this context the colors shown were mostly yellow/orange corresponding to material resistivities of about 1000 ohm.m, which is somewhat lower than a pure void (which in theory has an infinite resistivity, although in practice usually showing up as severa! thousand ohm.m). However there was definitely a well defined spatial anomaly, a sufficient distance below the surface that it could conceivably represent a discrete void within about 20 to 30 feet of the ground surface.. Furthermore this appeared also on the "isovolume" portrayal of the data, i.e. the zones of resistivity above 1000 ohm.m (in this case), a small-scale portrayal of which is shown adjacent. This also shows a smaller anomaly towards the South of the diagram, although evidently closer to the surface and of lesser extent. Such resistivity values of 1000 ohm.m. can also be encountered in intact rock, for instance. However, within the volume of material tested within these co-ordinates, this clearly highlighted the regions that were liable to be at- risk, and as a result, additional attention was directed towards this zone. This presentation to some extent allows the spatial co-ordinates of the anomalies to be pin- pointed more precisely for location of boreholes. Radar As part of the concern about the high resistivity zone shown in the geo-electrical results displayed above, the Ground Penetrating Radar was towed over this region. Significant radar anomalies were generally not encountered close to the surface on this block. However a near-surface anomaly was encountered at the North end of the block, an extract of which is shown adjacent - the full-size version of which is displayed in Figure 10. BCI Project 05-277 -0.0 -7.0 z -14.0 -21.0 32.064.09s.9 lronbridge Golf Club & Community Page 20 The co-ordinates of this point were approximately X = 14, Y = 91 (the units being in meters from an origin at the South-West corner of the block, the entire run extending north by north-east through the top left-hand corner of this block). Even though this point was not associated with a high resistivity zone in the previous three-dimensional electrical profiling, anomalies close to the surface are not necessarily detected very well by 3-D resistivity arrays, and so this represented a questionable area. As a result of the question generated by this trace, an additional gravity line (G2) as well as an additional borehole (hole B-3) were therefore specified for this area, and these are discussed in the following sections (although as will be explained shortly, the anomalies detected by drilling turned out to be in fact associated with subterranean boulder(s), rather than with voids). Near-surface radar anomalies were not otherwise noted in this area. Gravity As a further check, a gravity line (Gl) was run overthis area, from South to North, as shown in the plan view of this area in Figure 6, eoresponding roughly to a line X = 13 m on the resistivity block. A detai! of the results is shown adjacent, (a full-scale version of which is contained in Figure 1 1). The position of this line starts about 5m off the S end of the resistivity block. lt can be seen that there is a significant dip in gravity at about 30 m., followed by a trending high but a local low Gt o 6(9c = Eoo.: .! oE 0.25 0.2 0.'15 0.1 0.05 0 -0.05 -0.1 -0.15 -0.2 Distance, m at about 60 m., which corresponds roughly to the resistivity anomaly previously noted. Asaresult,aborehole(Al)wasdrilledatY=25m(i.e.30mfromthebeginningofthis !ine, corresponding to the first gravity dip), and this is described subsequently. BCI Project 0&277 lronbridge Golf Club & CommunitY Page 21 Based on the resistivity results, a second borehole (B-1) was also drilled at about Y= 65 m. on the resistivity grid, which in fact corresponds to a distance of about 70 m. on the gravity !ine, and in the benefit of hindsight probably corresponds to the gravity high (i.e. a subterranean boulder) at the North end of the line. The results of the resulting borehole are also discussed in the next section. Because of the radar anomaly noted above, a second gravity line (G2) was run at the NW end of the block, as shown in Figure 6, and the detailed results are presented in Figure 12, an insert version of which is shown adjacent. This shows a gravity diP at about 28 m. (90 ft.), so that an additional borehole (B-3) was also drilled in this vicinity, as can be seen on Figure 6, and this is also discussed in the following section. cI a a I I I 0.260 0.200 o. r50 0. t00 0.050 Drilling In order to investigate the higher resistivity anomaly noted at some depth in the inverted resistivity cross-sections mentioned previously, and as a result of possible concem about what could be a potential void below the surface towards the Southern end of the region surveyed (as indicated on the right-hand portion of the "iso-volume" diagram in Figure 9), and as a resutt also of the Ground-Penetrating Radar anomaly mentioned above, as well as some of the dips in the gravity lines, a total of three bore-holes were drilled in this area, as shown on the exploration plan (Figure 6). The deepest rotary bore-hole was drilled at X = 15, Y = 65 and denoted B-1. The log of this boring is included in the main figures as Figure 14, but the main item of interest is that the major subterranean geologic feature encountered at a depth of about 25 to 30 ft (Z = 7 to 9 m corresponding to the major anomaly in the electrical resistivity profiles) was a very large and hard boulder several feet in diameter. There was in addition another boulder beneath this, although this appears not to have registered separately as an electrical feature (or least was not sufficiently distinct to be distinguishable by the contouring sub-routines). Otherwise the strata contained gravels and silty sands, with BCI Project 05-277 lronbridge Golf Club & CommunitY Page 22 laboratory resistivities mostly testing in the hundreds of ohm.m, as might be expected from the cross-sections ("green" color-coding). An initial boring (A-1) was also drilled at local co-ordinates X = 13 m., Y = 24 m. relative to the origin of the 3-D rectangular resistivity block (namely the south-western corner of the btock), shortly after commencement of geophysical investigations in September, 2005. (This corresponded to the initial gravity low in the gravity line G1, as well as to a lighter-colored zone in some of the earlier data reduction, which can faintly be seen in the slice presentation in Figure 8). However at this time only auger drilling equipment was available, and as previously mentioned, this drilling method was less successful, and could only advance the boring to a depth of 16 feet below grade, at which point no indication of a void had been found, and drilling had met with refusal for the available equipment. The borehole log for this is shown in Figure 13 - the gravity low was probably caused by the lower density of the upper soils in this region, and a cobble- stone zone was recorded at a depth corresponding roughly to the top of the suspect orange zone, through which further drilling was not viable with the auger equipment. Since there was no further evidence for the existence of a possible void at this location, drilling here was then terminated. A third bore-hole (B-3) was drilled in the R1-R2 area at the site of the shallow GPR anomaly at the N of the block, and also at the site of the small local dip on gravity line G2, (corresponding approximately to local co-ordinates X = 12 m., Y = 90 m.). There was also a slight resistivity high in this region, although not of sufficient extent to have been considered remarkable in its own . right. The field log for this borehole is reproduced in Figure 15, and it was taken down to a depth of 30 feet, with large boutders being encountered towards the bottom of the hole. No void was encountered, and in general the prevailing soiltypes recorded were silts close to the surface, followed by gravelly sands, and river gravels deeper into the formation. These borings all remained dry at completion, indicating that the water table was some distance down, which undoubtedly contributed to the high resistivity readings. BCI Prqject 05-277 lronbridge Golf Club & CommunitY ZONE R3 Electrical Resistivity Profi ling As the next step in the process of investigating the subterranean conditions at the site, BCI conducted another three-dimensional "roll-along" survey over the area described in the overall location plan Figure 5 as Zone R3, and highlighted in pink on the adjacent graphic, which also again shows the position of the origin for the X and Y co-ordinates used to describe the position of any the measurements. The results of the back-analyzed sections produced in this area is shown in detai! in Figures scale used in the contouring system, as discussed previously. However it can be seen immediately from the inverted resistivity volumes (Figure 17A in particular, an extract of which is displayed adjacent) that there were two fairly substantial high-resistivity zones in the block diagram - namely along SW side. This is also evident in the "slice" presentation of the results, as well as in the "iso-volume" portrayal in Figure 19A, an excerpt of which is also shown adjacent. As a result, two boreholes were planned at block co-ordinates X = 4 m., Y = 6 m., and X= 4 m., Y = 55 m., as shown on Figure 16, the investigation plan for this zone. This corresponds to the highlighted orange and red areas on the resistivity figures, while the adjacent soils are mostly green in color, representing sands with resistivities of around 100 ohm.m or less, and even blue implying silts with maybe even some clay content. Further, a gravity line was planned along this Iine, as discussed shortly. BCI Project 0*277 17, 18 & 19, together with the color -6.8 -135 'so.Eo'2 70.0 lronbridge Golf Club & Community Page 24 Radar As part of the multi- technique investigative approach, the Ground Penetrating Radar equipment and antenna was also towed over zone R3, mostly in a North-West direction starting from the southern boundary. On one of these runs (corresponding roughly to X = 5 m. or 15 ft.) a slightly unusual near- surface anomaly was noticed, shown at reduced scale adjacent (and at larger size in Figure 20). (This corresponds approximately to the eventual position of borehole A3). Gravity As a further check, a gravity line (G3) was run over this area, running from SE to NW in the direction indicated on the area plan shown in Figure 16. The results are displayed on Figure 21, with a small- scale graphic shown adjacent. Although there is a noticeable dip in the gravity at about mid-distance, this in fact does not coincide with the "hot-spots" measured in the resistivity, and so this technique was in reality inconclusive G3 0.500 0.400 0.300 0.200 0.100 0.000 -0.100 -0.200 0istance, m here. ln the benefit of hindsight, there is actually a gravity rise over the beginning part of the line, roughly corresponding to first of the resistivity "hot-spots", which supports the later observation by drilling that this area is in fact dense boulders/cobbles. The line does not really extend far enough to reach to the second "hot-spot", which occurs at about Y = 55 m., and consequently neither confirmed nor contradicted the existence of possible low-density regions there. A couple of holes were therefore performed, as follows. BCI Project 05-277 lronbridge Golf Club & Community Page 25 Drilling As a fundamental check on the sub-surface conditions in this area, and because there were two relatively well defined anomalies in this area, two holes were drilled at the positions indicated on Figure 16, the lnvestigation Plan for Zone R3. The first borehote was denoted A3 and was drilled as part of the first phase of drilling in Sept. 2OO5 with auger equipment, at local co-ordinates approximately X = 4 trt, Y = 6 m. relative to the resistivity block R3. The boring log is shown in Figure 22. This basically encountered gravels down to six feet, at which point a large cobble-stone was encountered, and drilling was stopped when two drill teeth broke off. Since this appeared to be the explanation for the anomaly, drilling here was not extended deeper. The reason for the large red zone extending to the surface appeared to be a region of very coarse gravels/cobbles, which would normally be expected to produce a higher- than-average resistivity zone, particularly if relatively dry, or if containing relatively fresh pore-water with low concentrations of dissolved ions in the pore fluid. A second muchdeeper borehole was drilled with air-rotary equipment in Oct. 2005 to a depth of 30 feet, at local co-ordinates of approx. f, = 4 m., Y = 55 m., aS shown as boring B-12 on the plan of this area. The boring log of this is shown on Figure 23, and it encountered a major area of grave! with boulders from about 7 to 12 ft. (2 to 4 m.). This is likely to be the zone responsible for the high-resistivity region shown at the North- West end of the area surveyed in the resistivity work. lt is also probably responsible for the slight upwards trend of the gravity line towards the far (NW) end, although the line did not extend far enough NW to quite reach this region. The soil types then grade into silty sands, and eventually even some clayey silts. These correlate to the underlying green and even bluish zones at depth in the resistivity contours here, (corresponding to resistivities of a few hundred and less-than-a-hundred ohm.m respectively), particularly if the stratum is generally above the water table, as indicated by the drilling. ln general, both borings recorded generic soil types similar to those recorded in the earlier geotechnica! drilling by HP Geotech, namely sands and gravels with some silts mixed in, although there are evidently pockets of much larger material mixed into the geology, as might be expected from the fluvial history of the site. Since no evidence of voids was encountered at either of these two anomalous locations, further drilling in this region was not continued. BCI Project 05-277 lronbridge Golf Club & Community ZONE R4 - R5 Electrical Resistivity Profiling ln this region, BCI also conducted a three- dimensional "roll-along" survey over the area described in Figure 5 as Zone R4 - R5, and highlighted in green on the adjacent graphic. Again the position of the origin for the X and Y co- ordinates used to describe the position of any measurement or slices or anomalies etc is shown at the appropriate corner of the scanned area. The results of the back-analyzed sections produced in this area is shown in detail in the figures at the end of this report, together with the color scale used in the contouring system, as discussed previously. lt can be seen from the inverted resistivity volume (or "block diagram" presentation) shown in Figure 25, that there were a couple of significant high-resistivity zones in this region - most notably along the South side of the block (i.e. along the y-axis) at positions roughly of Y = 30 m. and Y = 60 m. An excerpt from this is shown adjacent, with two reasonably deep-seated zones of material of resistivity in excess of 1000 ohm.m., which is the value that was generally used in this investigation as an indication of potential void space. Figure 26 also shows this presented as a series of slices. However the most instructive presentation format on this occasion is the so-called "iso- volume" portrayal shown in Figure 27. On this occasion the "cut-off'value of resistivity used was 3,000 ohm.m., because the resistivity values were sufficiently high to justify this. ln this instance, this portraya I enables relatively accu rate positio n i n g. BCI Prqject 05-277 -0.0 -7-0 -f,+.0 -2L-OJ 9s.9 z -r4.0 -0-0 -7-O o-o o-o o-o o.o lronbridge Golf Club & Community Page 27 On the basis of these three-dimensional resistivity measurements, potentia! at-risk areas were identified along the Y-axis at about Y = 65 m. & Y = 25 m., and also around the area of X = 20 m., Y = 25 m., and these represented spatial anomalies of a sufficiently high resistivity and a sufficient distance below the surface, that they might represent voids. Radar Once again, as a general check against near-surface voids, the Ground Penetrating Radar equipment was used over the block of soil in question. Although electro-magnetic traces of the subsurface soil boundaries could be measured, in this region, significant near-surface evidence of voids was not seen by this technique, and so emphasis in this area was placed on the interpretation of the other techniques. Gravity As a further check, two gravity lines (G5 & GO) were run over this area, from West to East, as shown on Figures 28 and 29 (and shown also in detail adjacent). Both of these gravity lines showed a gradual increase in the level of gravity, as progressing from West to East, and with some local variations superimposed. G5 was the gravity line that was the further North of the two, roughly on a line corresponding to Y = 21 m. Although there were a couple of small dips in gravity, these did not coincide with the resistivity "hot-spot" measured previously, which actually was around 70 m. from the western end of the block (or about 30 m. from the eastern end, i.e. Y = 25 m. + 5 m. end length) and therefore in a region of a slight gravity high. lt was thus felt unnecessary to drill an additional borehole here. For gravity line G6, which was also run West to East but towards the South of the block (roughly on a line corresponding to Y = 5 m.), there were a number of noticeable dips in the loca! micro-gravity field. The first of these was right at the West end of the block, BCI Project 0&277 il, o.3ooIi.i o.zoo I ! o.roo .:I o.oooa E -0.100 -0.200 lronbridge Golf Club & Community which did not correspond to a resistivity high-spot, so a drill-hole was not planned here. However there were slight reductions in gravity around Y = 25 m. & 65 m. ( i.e. 25 & 65 m. from the right end of the line, once allowance is made for the fact that the line extended just off the end of the block). ln particular, at Y = 65 m from the right end (or about 35 m. from the left end), there appeared to be a significant reduction in gravity of about 0.1 mgal (or about 0.1 millionth of earth's gravity), so that it was felt prudent to plan drill holes in these two locations, as discussed next. Drilling ln order to investigate the two higher-risk areas identified above, two boreholes (B-10 and B-11) were drilled in the locations shown on Figure 24, conesponding roughlyto local co-ordinates Y = 65 m. & Y = 25 m. (with X = 5 m. approx.). The logs forthese are shown on Figures 30 and 31, and both show a zone of gravel and boulders about 2 m. (6 to 7 feet) below the surface, and extending for some depth beneath this. The zone of boulders in borehole B-10 appeared to be at least six feet thick, and below this there was gravel, although below this at about 25 feet the strata trended into clay with silt. Borehole B-11 appeared to have a zone of boulders about three feet thick (through which the Odex drill penetrated by using the down-hole pneumatic hammer drill system), but then a much more substantial zone of sands and gravels below this, until sandy clays were encountered at about 31 feet. This was presumably the explanation for the deep high-resistivity zone mapped out here by the electrical measurements, and shown as extending down to around 11 m. (35 ft.). As previously, samples were obtained from the compressed air chippings produced by the air-rotary process, as this drilling was performed without stopping for discrete soil/rock sampling, for increased speed and efficiency, as it was not considered necessary to recover individual samples in this application. No borehole water was encountered at either location, even though drilling went down to 30 and 40 feet respectively - this wil! have contributed to the high resistivity of the formation. BCI Project 05-277 Page 28 0.500 0.400 | 0.300t!I E 0.200 II t!. 0.100 .! I I o.ooo -0.r00 -0.200 lronbridge Golf Club & Community ZONE R8A Electrical Resistivity Profiling Likewise in this zone BC! conducted a three- dimensional "roll-along" sutvey over the area described in Figure 5 as Zone RBA, and highlighted in light blue on the adjacent graphic. R8A The origin for the X and Y co.ordinates used to describe the position of any measurement or slices or anomalies etc is also shown at the lower left corner of the rectangular surface projection of the scanned area. The investigation plan for this zone is shown on Figure 32, and the results of the electrical survey are displayed in a number of formats on Figures 33 through 35, together with the color scale used in the contouring system, as discussed previously. The block volume format in Figure 33 (an extract of which is adjacent) shows a number of high resistivity zones that were at least partially expressed on the adjacent ground surface, but it is not clear how deep these extended. As a result, the results were also presented as a series of vertical slices in Figure 34, (because the volume format only shows values on the external surface of the rectangular block), and this indicates that the high-spots roughly at values of Y = 20 m. & 60 m. seemed to be the more significant ones. -rq4; o'o o-o u'; However, this presentation was still not especially conclusive, and so an "iso-volume" portrayal of the data was utilized in Figure 35, showing the areas with resistivities above 1000 ohm.m in a number of orientations, in order to help visualize the positions of the higher resistivity areas. An elevation along the Y-axis is shown adjacent, showing z anomalies extending to a depth of about 5 m. (15 feet). BCI Project 05-277 -0.0 -6-8z -rs.s lronbridge Golf Club & Community A plan view of the same "iso-volume" data is also shown in the extract adjacent, which assists in highlighting the positions of the anomalies on the ground. A cluster of three high-resistivity areas is apparent towards the bottom of the block, approximately at co-ordinates (X = 4 m., Y = 15 m.), (X = 6 m., Y = 25 m.), and (X = 20 m., Y = 15 m.), and each of these points was subsequently investigated by drilling, as will be discussed shortly. There was also a cluster of points towards the top of the block, but only one of these was of substantial size, namely the one towards the top right corner (Northern corner) at co-ordinates roughly (X = 17 m., Y = 65 m.). This was also the deepest high-resistivity area in this region, extending to a depth of about 7 m. (22 ft.) or more. As discussed shortly, this became the location of the drill-hole drilled in this area, but in order to check the other spots, a radar scan was also caried out, as described next. Radar Because of the need to differentiate the more important anomalies from the less important anomalies, as detected above, the Ground Penetrating Radar was towed over this region also. Significant near-surface radar anomalies were mostly not encountered in this block, and not at the Northern end, so that the only point at the North end that it was felt worth drilling a borehole was the high-resistivity area at co- ordinates roughly (X = 17 m., Y = 65 m.) as mentioned above. However towards the Southern end of the block some minor radar anomalies were noted as the GPR equipment was towed from top to bottom along a line corresponding roughly to X = 5 m., and these are displayed on Figure 36 (an extract of which is shown adjacent), with two anomalies shown corresponding roughly to the final positions where boreholes B-7 and 8-6 were drilled. BCI Project 05-277 0-0 8.3 x L6.7 ?s-O lronbridge Golf Club & Community Page 31 Drilling As before, confirmatory drilling was carried out in this block, at the positions considered to correspond to the most notable anomalies. ln this zone, a total of four such holes were performed, which was the largest number of holes carried out any zone on this phase. ln this way it was possible to be reasonably certain that any ouestionable areas were fully investigated, and the positions of these are shown on Figure 32. These were carried out on October 18 and 19, and, as before, the drilling was performed by air- rotary drilling that permitted recovery of the soil thrown up by the compressed air return and/or any chippings that were created when the Odex down-hole air hammer had to penetrate cobbles or boulders too large to be blown up through the annular space between the drill and the casing. Logging of the soil formations was done on this basis, as well as laboratory classification of bag samples shipped to the BCI labs afterwards, although intact tube or core samples were not recovered under this procedure. The detailed logs of each borehole are presented on Figures 37 through 40 for these boreholes. ln general, the sub-surface conditions encountered were similar to those previously indicated, with silty sands and gravels being present. Borehole 8-6 encountered sand and gravel and cobbles from 2feetdown to about 12 feet, which is probably the main reason for the higher resistivities measured in this area, although between 5 to 7 feet very large cobbles were recorded, which will have resulted in unusually high resistivities (probably the red spots on the Southern portion of Figure 33). Borehole B-7 showed a very deep deposit of gravel, from close to the surface down to about 25 feet or 8 m. This is possibly the deep yellow plume towards the South of the zone in both the block resistivity presentations and the iso-volume presentations. Below this, the strata became siltier, which we believe would conespond to the predominantly green color contours in the surrounding material. Borehole B-8 also encountered sands and gravels from 6 to about 11 feet, which would also represent more resistive material, though not to the same degree as cobbles and boulders, which is likely to be why this region did not show up as prominently in the resistivity slices. Borehole B-9 however had a layer of sand with gravel from close to the surface down to about 17 feet, which is likely to be responsible for the larger size of the resistivity high in this region (although not necessarily higher individual values). !n all cases in this zone, the anomalies that were drilled turned out to be associated with coarse-grained deposits of gravels or cobbles/boulders, rather than with voids. BCI Project 05-277 lronbridge Golf Club & Community ZONE R9 Electrical Resistivity Profi ling As part of the process of investigating the subterranean conditions at the site, BCI also conducted a three-dimensional "roll-along" survey over the area described in Figure 5 as Zone R9, and highlighted in red on the adjacent graphic, which also shows the position of the origin for the X and Y co-ordinates used to describe the position of the measurements over the surveyed area. The results of the back-analyzed sections produced in this area is shown in detail in the Figures 42 through 44 at the end of this report, together with the system, as discussed previously. !n this case it can be seen that a block volume portrayal (excerpted adjacent) shows one main high- z resistivity anomaly, along the middle of the Western side (although not very deep) together with a smaller one further north. This is confirmed by the presentation as a series of slices in Figure 43 (since the block presentation only shows values on the surface of the rectangutar figure portrayed), which shows a more concentrated higher-resistivity "hot-spot" at about the mid-point of the slices, and probably about 5 m. (15 ft.) thick, as can be seen image. The values of resistivity shown here were not especially high, being on the order of 200 to 500 ohm-m (represented by the yellow/orange Z colors here), and are typically indicative of reasonably dry sands and/or sandy gravels. However this region was obviously the major significant anomaly in the region, deserving further study. BCI Project 0*277 from the adjacent smaller-scale -0.0 -7.0 -14.0 -0_0 -7 -O -14-0 -2t_o 9s. 6.0 x color scale used in the contouring 0.0 0.0 o.oo.o tzo 18- lronbridge Golf Club & Community Page 33 As a resutt, an "iso-volume" presentation was again utilized, showing the areas of resistivity over 1000 ohm.m. in Figure 44. As can be seen in the adjacent extract, the same zone can be seen in about the west mid-point of the block, only it was in fact quite shallow. There was also a smaller high- z resistivity anomaly towards the north of the block. Study of a plan portrayal of the iso-volume presentation showed that the major anomaly occurred at approximately co-ordinates X = 6 m, Y = 45 m., and this can be seen on the other views of the iso-volume in Figure 44 - i.e. looking horizontally eastwards in elevation. Radar '2u8.6 looking from above in plan, and also As part of the concern about the high resistivity zone shown in the geo-electrical displayed above, the Ground Penetrating Radar was towed over this region. Significant radar anomalies generally -0.0 ' -7.0 -L4.O izo r8.o o.do.o 6'0 not to theencountered close surface on this block. However, a near-surface anomaly was detected at the North-East corner of the block, and this is shown on Figure 45 (with a detail above). On this occasion, this did not obviously correspond with a high-resistivity anomaly detected previously by the 3-D resistivity work, but the reflector was sufficiently pronounced that it was felt to merit attention. The radar anomaly appeared to be at a depth of about 7 to 8 m. (20 to 25 feet), and at the NE corner of zone R9 (the horizontal units on the radar run were from the beginning of the run, which was actually performed diagonally from the South-West. A borehole was therefore subsequently planned for this area (borehole B.4, as indicated). BCI Project 05-277 lronbridge Golf Club & CommunitY Gravity As a further check on the possible presence of voids in this zone, a gravity line (G4) was run over this area, approximately from South to North as shown in Figure 41. This particular line was relatively short at only about 15 m (50 ft.), and was designed to run over the resistivity anomaly previously detected. A detail of the results is shown adjacent, (and again a full-scale version is contained in Figure 45). As can be seen, this gravity line showed substantial swings in the local micro-gravity, with a local high at about 6 m. followed by a local low at 9 m. followed by an even larger high at 11 m.. Basically, this line was felt to be inconclusive, because of these large swings and the difficulty of pin- pointing individual highs and lows at such a relatively narrow horizontal scale, but it did confirm the desirability of further investigation here. Drilling As a result therefore of concerns about the high resistivity anomaly on the west side of the block, and the radar anomaly at the NE corner, invasive geotechnica! boreholes were drilled at two locations in this zone, as shown on Figure 41. Borehole A2 was initially drilled with an auger rig at the NE corner, but could not progress past a depth of 17 feet because of the presence of cobbles there (the relevant borehole log is shown on Figure 47, showing sands and gravels at the surface). Borehole 84 was later drilled adjacently with an air-rotary drill to a depth of 30 feet, and the full borehole log for this is shown on Figure 49. Again sands and gravels are shown in the top layer, progressing to gravels at about 14 feet, but then encountering large boulders from about 21 teet. These large boulders were recorded down lo 27 feet, and were presumably the cause of the radar reflector measured previously. Borehole 82 was drilled with the Odex air-rotary drill at the site of the high-resistivity anomaly, and this boring log is shown on Figure 48. the hole was drilled to 30 feet (which was well below the depth of the anomaly detected). This did not encounter boutders, but did encounter a layer of very dry gravel with some sand about 6 to 8 feet below the surface. This was surrounded by slightly more conducting silty sands, so this relatively resistive area was presumably the explanation for the higher-resistivity zone mapped out by the electrical measurements on average about 3 m.below the surface. BCI Project 0*277 0.05 0.04 I0 0.03 a ! 0.02 I! o.orl!t-tU | -o.or E -0.02 -0.03 lronbridge Golf Club & Community ZONE RlO Electrical Resistivity Profi ling ln this region also, BCI conducted a three-dimensional "roll-along" sulvey as part of the process of investigating the subterranean conditions at the site. This was carried out over the area described in Figure 5 as Zone R10, and highlighted in orange on the adjacent graphic, which again shows the position of the origin for the X and Y co-ordinates used to describe the position of any measurement or slices or anomalies etc., and is shown at the lower left corner of the rectangular surface projection of the scanned area. The back-analylzed geo-electrical results produced in this zone are shown in detail in Figures 51 through 54 at the end of this report. However it can be seen from the block diagram presentation shown adjacent (and in both a top and bottom view in Figure 51) that there were two major high-resistivity anomalies in this block. The first of these was at the South-East end, and the second was at the North-East corner. The significance of the colors and the resistivity values has already been discussed, and in this context the ambient colors shown were mostly green Z (corresponding to silty sands) with orange and red in the anomalous areas (corresponding to material resistivities of over 1000 ohm.m, which is normally either indicative of a void (which in theory has an infinite resistivity, although in practice often showing up as several thousand ohm.m), or of a very non-conductive coarse soil such as unsaturated gravels/cobbles or of a boulder). -0.0 -5.8 -13-5 -20-21 69_9 ln any case, there were definitely two well defined spatial geo-electrical anomalies, a sufficient distance below the surface as to represent the possibility of discrete voids. These are also visible in the "slices" presentation in Figure 52, although their position is not especially clear in this visualisation. BCI Prcjed 05-277 o-o o-o lronbridge Golf Club & Community Once again, a clearer geo-electrical representation of the anomalY positions in space was possible Z through the "iso-volume" presentation shown in Figures 53 and 54. The two higher-resistivity "hot-spots" can be seen from these figures, which (if reference is made to a plan view) are centered around (X = 25 m, Y = 10 m.), and (X = 25 ffi., Y = 65 m.). Page 36 :::I; aaaa ::.: aaaa aa I I'rl..i. .t 0.0 10.o 20.0 30.(x 0.00.0 ru'u x using zones of resistivity z -0.0 -6.8 -13.5 ln this case, an additional iso-volume portrayal was made above 3000 ohm.m. which is shown in Figure 54, and represents a much smaller and more concentrated volume of material, so that the spatial co-ordinates of the anomalies could be pin-pointed more precisely for location of any boreholes. An extract of the plan view of this is shown adjacent, showing the same basic anomalous zones. Such resistivity values are at the upper end of the normal measuring scale, and can also be encountered in very coarse soi!, but within the volume of material tested within zone R10 (and defined by these co- ordinates), zooming in on the highest resistivity areas highlighted the regions that were liable to be at-risk, enabling additional attention to be directed towards these zones. Radar As part of the concern about the high resistivity zone Y 69.9 46.6 23.3 0.o shown in the geo-electrical displayed above, the Ground Penetrating Radar was towed over this region but significant near-surface anomalies were not generally noted in this atea, although electro-magnetic traces of the subsurface soil boundaries could be measured. Emphasis in this area was therefore placed on the interpretation of the other techniques. BCI Project 05-277 lronbridge Golf Club & CommunitY Gravity As a further check, a gravity line (G7) was run over this area roughly from South to North as shown on Figure 50, with the results disPlaYed on figure 55, and also shown at reduced scale adjacent. More precisely, the line proceeded from a SSE to a NNW direction, and extended about 5 m. off each end of the block shown, These measurements were not particularly helpful in this case, as there appeared to be considerable variation upward and downward about the mean value. The geo-electrical anomalies actually appeared to correspond to slight gravity highs, with the South one occurring about 10 m. from the left end of the gravity line, and the North one occurring about 5 m. from the right end of the gravity line. Drilling lnvasive drilling was once again undertaken to confirm the sub-surface conditions at the two anomalous locations in question. Borehole B-13 was drilled towards the North-East corner of the btock, and (as shown in the boring log on Figure 56) encountered grave! w1h sand and boulders from close to the surface down to about 8 feet (3 m.). This was likely to correspond to the material in the top right red zone on Figure 54, as might be expected. Below this was sandy silty clay, which would have much lesser resistivities. The hole was carried on to 30 feet, where moist clay was encountered, although the boring remained dry during drilling, with no seepage water encountered to this depth. Likewise, borehole B- 5 was drilled in the vicinity of the South-East corner of the block, and this time was carried on to 40 feet, since the anomaly in this area appeared to be somewhat deeper. However again no voids were found, although dryish sands with gravels were detected from about 4 feet down. A discrete zone of gravel (of moisture content only about 1 Yo) was encountered at 1 1 to 13 feet, which is likely to represent the deeper more resistive material in this region. Also a gravel layer was encountered below about 31 feet, although in between the soil stratum appeared to be mostly less resistive sandy silt, which will map as green colors. ln both cases, discrete voids were not encountered. BCI Project 05-277 uI a T a a lronbridge Golf Club & Community Page 38 FINDINGS 1. BCI understands that there is a general concern at this site, concerning the potentia! for sinkholes and underground caverns in the subsoil, particularly as the site is known to be underlain by layers of evaporite containing potentially soluble gypsum minerals, and that some sinkholes have been observed close to the surface in the area. 2. The use of three-dimensional multi-electrode resistivity testing (which BCI has previously found to be an effective means of detecting sub-surtace voids in karstic ground), showed the site to be underlain by a number of areas with resistivities in excess of 1000 ohm.m., which is a relatively high absolute resistivity in comparison with most soils, and could normally be indicative of potential voids. However large portions of the site were also underlain by fine silts and clayey silts, which displayed resistivities of the order of 100 ohm.m or less, but generally above 50 ohm.m.. Sub-surface resistivity values were higher than usual across the site. 3. 3-D geo-electrical exploration was used as a primary means of identifying potential anomalies for further investigation - mostly areas with well-defined sub- surface resistivities of above 1000 ohm.m (or in some cases above 3000 ohm.m.). Several such anomalies were identified in each of the six zones scanned in this investigation, although anomalies of this level could also be zones of very coarse gravels, or massive rock, which will also sometimes display resistivities in excess of 1000 ohm.m. These were illustrated in several different methods of presentation in the appropriate figures, and enabled further investigation to take place. 4. Ground penetrating radar (GRP) was then used as a secondary method of detecting anomalies, especially any that might be very close to the surface, (as the large electrode spacing of around 4 to 5 m. used in the multi-electrode scans meant that small near-surface anomalies might not easily be resolved by electrical means). The use of GPR did not show obvious evidence of subterranean voids, although there were several area where subterranean reflectors were measured. These were mostly fairly weak by the standards of most subterranean reflectors, and in general there were few areas where indications of possible discrete voids were detected. These were recorded for further attention, in conjunction with the other geophysical information. 5. Gravity measurements using a Lacoste-Romberg gravimeter were also run along selected lines in the zones, to a precision of about one part in a hundred mi!!ion, as under these circumstances a sizeable void should cause a measurable gravity deficit (although it should be noted that lower density soil strata Iike silts and clays can also cause a localized reduction in micro-gravity). These results were used in combination with the previous data, to decide where to drill conventional bore holes. BCI Proiect 0*277 lronbridge Golf Club & CommunitY Page 39 6. As a final check on the possible sub-surface presence of voids, rotary drilling was used to advance physical borings through anomalies that had displayed geophysical properties that might be associated with a potential void. These boreholes were mostly advanced to depths of around 30 to 40 feet, and used air rotary equipment that permitted the soil types to be classified, and some measurements to be made on the disturbed material. However, on every point on this phase where a drill-hole was advanced, the anomalies at this site were found to correlate with boulders or cobbles or azone of high-resistivity overburden such as unsaturated gravels. 7. The general conclusions therefore at this site, was that the areas covered by the geophysical/geotechnical investigations did not indicate the presence of voids or sinkholes to the depth of penetration of the investigation - i.e. 30 to 40 feet. B. As a generic genera! geotechnical observation, the site is underlain predominantly by unsaturated coarse soils (cobbles, gravels and sands) that have a relatively high absolute resistivity in comparison to most sites. This is probably accentuated by the very pure pore water present here, that will contain a very lorar level of dissolved ions and will therefore not be as conducting as most pore water. Many concentrated zones of high resistivity material were observed, and these mostly appeared to be due to pockets of extra coarse material like cobbles, or in some cases to discrete massive boulders of highly resistive rock. These displayed values of resistivity comparabte to what might normally be expected for a subsurface void - i.e. in excess of 1000 to 3000 ohm.m., showing up as extremely high resistivity anomalies. g. lt should be noted that this geophysical/geotechnical investigation was directed specifically towards the detection of subsurface features indicative of potential sinkholes or underground caverns, and not for the basis of foundation design or any other engineering design function. Bearing capacity design, or basement wall design or other design functions are not addressed in this report, and are the responsibility of the client's design engineers. 10. Although significant underground voids or caverns were not detected in this investigation, the opinions contained in this report do not guarantee against the presence or absence of voids and/or future ground movements. BCI also reserves the right to modify or change opinions in light of new information provided at later dates. BCI Project 05-277 lronbridge Golf Club & CommunitY Page 40 LIMITATIONS This Site lnvestigation Report is based on information supplied by the owngr and/or others, and a visual survey of the elements exposed to Bryant Consultants, lnc. at the time of the field investigation. Bryant Consultants, lnc. cannot be responsible for knowledge of subsurface conditions substantially away from the borings and profiles. The boring and profile locations were approximately determined by GPS readings a.1d by tape measurements from existing piysical'features, and should only be considered accurate to the degree implied by the methods used. Geophpical inverse methods are subject to errors and interpretation away from the profile line.. Environmental enois may result in in-exact data which will provide some variation in the theoretical resistivity models after inversionsbf the same data sets. Non-uniqueness of the inverted data also may produce similar resistivity structure models using different raw data sets. Use of resistivity coupled with control information from borings including true- resistivity m-easurements of the soil samples, identification of stratigraphic boundaries and the presence of groundwater greatly enhance the electrical resistivity tool' The conclusions and visual observations of this report are based in part upon the data obtained in the measurements and borings and upon the assumption that the soil conditions do not deviate from those observed. Any latent distress in areis not eiposed cannot be anticipated without further destructive and/or intrusive testing. Unlnticipated soil conditions are commonly encountered and cannot !e fully determined by soil sam.ples, test borings, or test pits. BCI further assumes inat tne conclusions drawn from this information are based in part on intoniaiion gathbred by others. Fluctuations in the level of the groundwater may occur due to variations in rainfall, temperaturei, and other factors not present at the time the measurements were made. Samples obtained during the field operations will be retained 30 days after the issue date on the report, After this period, we will discard the samplis unless otherwise notified by the owner in writing before the end of this period. The observations, discussions, recommendations and conclusions in this report are based solely on the September and October 2005 geotechnical and geophysical explorations. lf any additional information becomes available, then BCI reserves the right to evaluate the impact of this information on our opinions and conclusions and to revise our opinions and conclusions if necessary and warranted after review of the new information. The observed conditions aie subject to change with the passage of time. This report does not constitute a guarantee or warranty as to future life, periormance, need for repair or suitability for any other purpose at this site but is an evaluation only and design and'implementation of any iepairs are responsibilities of others. This investigation was pgrformed by Bryant Consultants, lnc. and the 6ngineer in a manner consistent with that level of care and skill ordinarily exercised by members of the profession currently practicing in the same locality under similar conditions. The performance of desion enqineerins or other desiqn-related.functions. i,ncludino strugluril or f99n4atio4 evetopment ot qeotecnnical de?ig! paraqpters. are spqgifica=llY nol hclude4icope of work. Such desiqn activities are the responsibilitv of the desionated desion enqineer(s) on the proiect. Unless otherwise indicated, this geotechnical report was prepared exclusively for lronbridge Golf Club & Community and expressly for purposes indicated by for lronbridge Golf Club & Community. Permission for use by any other personi for any pJrpdse, or by for lronbridge Golf Club & Community fgr g different purpose must be provided by bryant Consult-ants, lnc. in writing. lt was beyond the scope of work of this report to address any environmental issues, if present, at this site. Anv use made of this investioation and/or the conclusions and recgmFend?tipns conFined her?in an{alv itv suliect to tfre fottowino limitation of llabitiW: ln ,regoonition of the relative risk and benefits of the oroiect to user and BCl. the riqks have b-een allocated sqch tha! user aorees. to, the fuilest exteni permitted bv taw. to limit the liabilitv of BGI to user for anv and il! ,cE!ms. !9sses. coFts. ever or claims expenses from anv cause or causes. incluJino attorney's fees and corsrtsr and exoen witness fees and costs. so that the total aqgregate liabilitv of the BG! tg gser sh3ll not exceed five ttrou# doitars ($5.OOO.OO) unless othenrvise specificallv aqfeed !n writi4s. lt ii inten9ed that ffi anv ind all liabilitv or causes of action however ?lleEg9 or ariiino. unle?s otherwise p,rorfribited bv law. For the purpose of this provision. BCI shall include the gtficers. difectorg. shareholders. partners; asents; servants and emplovees of BCl. This limitation is applicable to BCI's neotiqence or other fault in whole or in oart. BCI Project 05-277 {3.r. ,; l-?' l,lOHIH Locotion Plon Approx. Scole: 1": 2mi. RYANT 2033 Chenault Dr. Suite 150 Ganollton, Texas 75001 Ph. (972) 713-e109 FAx (972) 7159171 figure job no. 05-^77 by SMA insp. s/8/os I ron b ridge_Qevgl op m enl- 410 lronbridqe Dr Glenwood Springs, CO l 1!r ft / t=' 1f i( "- rl,:\ \. .t -,rl lt., --. t;((J ojj qi{t;l tD l,lOHIH Approx. Scole: 1": 1500' Sn8nlColufrnb,IE RYANT 2033 Chenault Dr. Suite 150 CarmlJton, Texas 75001 Ph. (972) 713-9109 FAx (972) 713-9171 figure 2 pb no. 05-^77 by SMA insp. 9/8/05 lronbridqe Development 410 lronbridqe Dr Glenwood Springs, CO tD NOHIH Areo Rock Geology Approx. Scole: 1"-- 4mi. Bryant Consulhnb, lnc RYANT 2033 Chenault Dr. Suite 150 Canollton, Texas 75001 Ph. (972) 713-e109 FAx (972) 713-9171 lronbridqe Development 410 lronbridqe Dr Glenwood Springs, CO figure 3 jnb no. 05-^17 by SMA insp. 9/8/05 tD l.lOHIH Areo Soils Geology Approx. Scole: 1": 1000' &yant Consulbnq hc RYANT 2033 Chenault Dr. Suite 150 Canollton, Texas 75001 Ph. (972) 713-9109 FAx (972) 713-9'17'.1 figure lob no. 05-477 by SMA insp. 9/8/05 lronbridoe DeveloPment 410 lronbridqe Dr Glenwood Springs, C0 YIII.Is (4? rural uxr 85(F20C VIIIJS (,[? loT& Irilng) Note: GilMIR Profle locotioaa ore opproximote SCALE: 1":150' Endcollalffi,hq RYANT 2033 Chenault Dr. Suite 150 Canoltbn, Texas 7500'l Ph.(972) 71S9109 FD( (972) 713-9171 lronbridqe Develooment 410 lronbridqe Dr Glenwood Springs, CO figure 5 job no. 05-^77 by SMA insp. 9/8/oS 298 NOHIH Note: GMMIR Profile ond Boring Locotlons ore Approximote SCALE: 1":60' &Yantcomdbnb, hc. RYANT 2033 Chenault Dr. Suite 150 Canolfton, Texas 75001 Ph. (972) 71&9109 FAx (972) 713-9171 figure 5 .it$ no. 05-^77 by SMA insp. 9/8/05 lronbridoe Development 410 lronbridoe Dr Glenwood Springs, CO GMMIR Profile R1-R2 {.0 -7-O -14-0 -?d*d 0-0-0.0 -7.O -14.0 -21-0 5000.00 4000.00 3000.00 2000.00 1500.00 1000.00 750.00 500.00 350.00 2,5.@ 150.00 100.00 75.00 60.00 45.00 30.00 20.00 15.00 10.00 7.50 Fiqure 7A lnverted ResistivitY Volume o-o o-o Figure 78 lnverted ResistivitY Volume EI EEo -z ..2ootr (6o o -!9UJ 5.00 36-0 24-O LLO o-0 x Figure 8A Static Vertical Slices 96.0 36-0 Static Vertical Slices GMMIR Profile R1-R2 5000.oo 4000.00 3000.00 2000.00 1500.00 1000.00 750.00 500.00 350.00 2.5.@ 150.OO 100.00 75.00 60.o0 45.00 30.00 20.o0 15.00 10.00 7.fi 5.00 EI E !o E .9ttotr 6(, L C'otr s$0 -7.D -1,1-0 -21-0 o-0 1e0 ?A-o 38.0x GMMIR Profile R1-R2 Figure 9A lsovolume > 1000 ohm-m-0-0 -7 -O -14-0 -r0#, Fioure 98 lsovolume > 1000 ohm-m Plan View 96-O 6+-o 32.0 so00.00 4000.00 3000.00 20@.00 1500.00 1000.00 750.00 s00.00 350.00 2s.@ 150.0O 100.00 75.00 60.00 45.00 30.o0 20.00 15.00 10.m 7.50 s.oo EI EEo .9ootr (!o L C'otr Z 0-1 .1il0 0-0 1e0 x ?A.O 36-0 Figure 9C lsovolume > 1000 ohm-m -0.0 -7.0 -14-O -21-o Zone R1-R2 Rodor AnomolY (Under Borehole BJ)\- BnanlConsllltsr|G hc RYANT 2033 Chenault Dr. Suite 150 Canollton, Texas 75001 Ph. (972) 713-s109 FN( (972) 7'.13-9171 lronbridqe DeveloPmd 410 lronbridqe Dr Glenwood Sprinqs, CO figure 10 job no. 05-^77 by SMA insp. 9./3.,1-95- a Go E i.= c,Lo o rh, -gotr 0.25 0.2 0.15 0.1 0.05 0 -0.05 -0.1 -0.15 -0.2 Distance in m. from beginning at S end Fiqure 11 - Gravitv Line G1 c,(, E >.E (E (9 o G o E, Distance in m. from beginning at SSW end 20 30 40 Fisure 12 - Gravitv Line G2 Eoc 1- I NE s *m FF ,6o r9ii EIil g dF,l Brvant Consultants, lnc.' Dallas, TX LOG OF BORING A.1 Proposed lronbridge DweloPment 410 konbd<lge Drtve Glenurood Sprinss, Colorado 81601 Date Drilled Ground Ele\Etion Casing To Drllling lvlelhod 9n4n0rl5 Existing Grade NA Cont. Fligltt Auger 'N = Standard Penelrallon Tod -T.= t{odined Cone Mbn Tec{ BCt{Fz77 llonbridse Golf Glub & Mour*ain Community Dsilh in feet 6 .Ct E o .YooE .Eo oCLtr oEEoo o o o g DESCRIPTION a Edr Co(., g o6 = I E -9 * trf.o a EJ =SIJ t E J ll i,, 16 TL a Iot,c; I ot .Eo a jooo6a{t IDciio(E o- a co .9 =GI tDtr ]Do ,lU o- l! CL c.9o o oU' EoF U' j Eo oc!)o- !tG!0.I o dotr^ EFtdE.o.ctr9 d E C}()G Eg EBOE'oo )o a EG a e2 6IL ol 1J : 2:. :,l 4- . 5- :'6- 7- : 8- .o- 10: 1l- 12- . 13- 14- . 15- 16- 17- t8- Pale Yellowish Orang Small to Medium size GRAVEL wtth brovrn dustY sand. LQht Bromr to Moderate Brorvn Dusty SAND. Buing Terminated at'15 Feet Due to Big Cobble- Stme. Notei No sryge u,ater encountercd during dri[irq. Bodr€ r€dned dry and caved at t 3 feet- Figure 13 o fi 3II N6o d FN ry6I o =Io8Io t 6I Bryant ggil*yt|3its, rnc LOG OF BORING B-1 Proposed lronbrirtge Development 4:10 konbklge Ddrre (Rec Center) Glenuood Sprirgs, Cohrado 81601 Date Drillsd Gromd EleYation Casing To Ehilling [r€thod 1U17n(fJ6 Existing Grade Completion ODEXAiT Rotary *N = Standard Pen€tralion T€d 'T+ iJHiSed Cone FeD8trstim T€|st gcl&.zn lronbrirtse Gof Oub & Mounhin Community Depth in f€d 6lt E U' .YooE '6 (rt o)o-Fo IL E.oa 6 3 C' g DESCR!PTION a Eo cooo =fro = 8. E .sr E c:) bo Iv EJ Ea.sJ I EJ .9o!o. t xotE (, U'slr a joI(\:ll EDc.'ao lEo- * Eo .9 C',1 CDEoo6r TLo. co E =o oo a oF fi! j Eo oc,or E'co ! 2fiooG,^ €FEEottrg ri Eoo6r8-!,v EEDOEoo )o, a c6 o g:{!IL 0: 1- 2- 3- 4- 5- 6- 7- 8- 9- 10- 11- 12- 13- 14- 15- 16- 17- 1E- 19-n- 21- 2.- %- 24-x-n- 27-8-a- 30- 31- 32- 33-u- 35- 36- 37- 38- 39- 4- 41- 42- 43- 4- 45-6- 47-8- E xl E x rvl Pale Brown to Moderate Yellowish Brovn SAND with oravel GILL). Grayish Orange Medium to Small Size GRAVEL with sand. 5 I 9 10 4 136.1 112.5 553 s2.3 26E.5 fvloderate Yellqdsh Brorn, Pale Broryvn to ModeraE Brown SILTY SAND wih gravel. Brownish Grayto Pale Brown Medium to Large size GMVELtlvifit sand. Large Very Hard Boulder From 26 to 32 Feet. Large Very Hard Boulder From 35 to a9 Feet. Boring Schedub to and Terminated at 41 Feet. Ndei No seepage waterencountered during drilting. Boring resnained dry and uncarred at coEpletion Figure 14 I (l! FNqloo Fts 6o6ItroooN o- )) I v LOG OF BORING B-3Bryant BSil,s,Y l+Tts, I nc Dat€ Drilled Ground Elevalion Casing To Ddlling iibthod :1U18|2AN : E isting GIade : Compldion : ODEXAiT Rotaty 'tl = Standard Penotratbn T€st *I- tdodiffed Cone PeDetrslion TeEtProfed lronbridge DeveloPment a1O konbridge D*ve tPropmed Rec-Cent€r) Glernnood Springs, Colorado E1@1 a .EJ e ETJ lrod€rate YdkilYish Brown, Pale Brown to Light Brwtrnb Moderate Brcwn SILTY SAND' iettowistr Gray ilrledium to Small Size GRAVEL with Moderate Broum to Moderate Yellodsh Brorvn SILTY CLAY with sand and gravel. Moderate Yellow{sh Brcwn to Graylsh Orange SILTY SAND wlttt ferv gravel (At deflh 1+15 hrge gravel) Molsture content apparently vuetter here' Brwtrnielr Gravto Pah Brown lvbdium to Large size Well-Gr.ited GRAVEL with sand. Large Boulders Present. Bodng Schedde to and T€minded at 30 Feet. Notei No seepege water encoulrtercd during drillirg. Botir€'renraineO dry and uncaved at csnpEtim. F(rure 15 31 0 o - NOHIH lnvestiqotion Plon. Zone RJ Note: GltMlR Profile ond Boring Locotlons ore Approximotc SCALE: 1"=60' RYANT 2033 Chenault Dr. Suite 150 Cardllon, Texas 75001 Ph. (972) 71&s109 FD( (972) 71i9171 figure 16 pb no. 05-^77 by SMA insp.9fEf05- lronbridoe Development 410 lronbridoe Dr Glenwood Springs, CO GMMIR Profile - R3 Figure 17A I nverted Resistivity Volume Fiqure 178 lnverted Resistivity Volume 5000.00 4000.00 3000.00 2000.00 1sm.00 1000.00 750.00 500.00 350.00 2.5.@ 150.00 100.00 75.00 60.00 45.00 30.00 20.00 15.00 10.00 7.50 5.00 EI EEo 't .t2oot (E .9L C) -g UJ o.t -6-7 Z -13.5 -20-2 1.0.0x 0'0 30.0 -0.0 -6-8 Z -13.5 Figure 18A Static Vertical Slices o-o o-o 10-0 x Fiqure 188 Static Vertica! Slices -20-2 -69.9 \ EI E.co .E al,'-o o)t Eo L()otr 1 1 75.00 60.@ 45.00 30.00 20.00 15.00 10.00 7.50 5.00 0.04-0 -6.7 -13_5 -2A-2 20.0 10.0 0.0x Fiqure 19A lsovolume > 1000 oh -0.0 .6-8 -r.3.5 i -20.2 30-0 Figure 198 lsovolume > 1000 ohm-m Plan View Z -4,t 750.00 500.00 350.00 225.N 150.00 100.00 75.00 60.00 45.00 30.00 20.00 15.00 10.00 7.50 5.00 EI EEo '5 aD'6ot (!o.E o -9tU 0.0 10.0 20.0 30.0 x Figure 19C lsovolume > 1000 ohm-m aaaa aala aaaa aaaa aaa. aaat aata aaaa RYANT 2033 Chenault Dr. Suite 150 Canollton, Texas 75001 Ph. (972) 71&9109 FA,\ (972) 7159171 BrYantConsdbn& hc (Y)lol oltrl =l>l*rl >t(ElL.I ?lFINI olt-I5l EI LI E' o IIJ U' G E') .E 'a o.o Eo i .= o(, =G .9o OOc!oI Oos CJ I oood oo o ooolo Oo a?o oono oOqo legu'l(1;rerg a^!]ElaU .i T eNtscIoo o{dt FF {!o o E @ooI o. oa B Bryant BSilj,yBits, lnc LOG OF BORING A.3 Proposed lronbridge DevebPment 410 lronbridge Drive (Lot 316) Glenwood Springs, Colorado El601 Date Drilled tgn4fzAfE 'N = Standard Penenrdion Test Grouncl Elmtion : Existing Grade 'T= i,lodl$ed cone Penetration TeEt CasingTo :M Drilling ,l/ldhod : Cont' Flight AugerBct{6.zn lronbridoe Golf Club & Mountain Gommunity Deplh in fset EltE ax(,ou '6a o CLFo-oEoa 6 o o g DESCRIPTION s c o, eoo 0, a .AE = coIL s CD E cl ao a .EJ =-gJ * .EJo6 IU o- a xoT'c ;o {, .Eo- a jooc,Nl* EDC6ooo- a co ^s =ot EDc.Eo(Ur l! CL c.9Io o aD 6o o j Eg ogoo- EoI ltoot^ €F6€OEul {, + 3a9v E6OEoa) )a I Eg at g Eal! Grayish Orange Medium to Large Size GRAVEL wih lbht brown dusty sand. Borirfg Terminated d 6 Feet Due to Big CobbFStone (Broke ttre ddlling bit teeth). Note- No seepage weter encountered during drilling. Boring rctmirrcd dry and uncaved at compEton. Fqure2. Bryant Bgp"ty !+fl ts, I nc.LOG OF BORING B.12 Proposed lronbridge DeveloPment 410 lronbrirJge Drive (Lc[ 313 Rec Center) Glenurcod Sprinss. Colorado 81@1 D€|le Drilled | 1qz:O?OcE 'N = Standard Penetratirn T€st Ground-Elevation : Exiding'Grade "T= lt/lodifi€d Oone Peseffiion Ted Casing To : ComPleiion Ddlling ]ll€thod : ODEX Air RotarYBCI{E.277 lronbridge Golf Club I Mountain Conmuni$ ryt in fee{ olt E o .Y(,oE Ea 6'o- F o CL Eoa 6 o o g DESCRIPTION a cocoo o, =o'6 = 8. .c CD g c J ao a EJ =ETJ a E Jo t, -go- a xo1's .9 d' -gr s j aDI(\I*r (D E'an ooo- a co o =GI Eooor IL.L coa =o oo GoF eo j Eo oco&EEo- IooE^ €FAEogfi9 +i,e;&p- =E =ED,c>o ,o s Eg a, gg orL o- 1- 2- 3- 4-. 5- o- 7- 8- o- 10: 11- 12- 13- 14- 15- 16- 17-. 1E: 19: n- 21- D.- T3- 24- %- 2f.- 27- %- E- 30- 31: 32- 33- u- 35- u x rxl wloderate Yelltrvish Brwvn, Pale Brown to Moderate Brown SILTY SAND with gravel (FILL). Light Bromto Moderate Reddlsh Brown SILTY SAND. Yellowish Gray b Grayish Orange GRAVEL with sand and boulderc. 6! ?i tEo- b .i 3o eNN.loo N d ! ry 8 o =Go 3 ry L[ht Brown to Grayish orangp SILTY SAND u,fth ferv gravel. Moderate Bror,vnto Ligfrt Brovrn CLAYEY SILT with sand. Boring Schedule to and Terminated at 30 Fed. Nctei No seepage water encountefed during drilling. Boing remained dry and uncaved at completion. Figure 23 R4-R5 I i \r so2 (D ].IOHIH lnvestiootion Plon. Zone R4-R5 - Note: GMMIR Profile ond Boring Locotlons SCALE: 1":60' 313 98 -/ Approximote lronbridoe Development 410 lronbridqe Dr Glenwood Springs, C0 figure n4 by SMA insp. BryanlCo.rudbils, hc RYANT 2033 Chenault Dr. Suite 150 Canollton, Texas 75@1 Ph. (972) 713-9109 FA|)( (972) 713-9171 GMMIR Profile Fioure 25A lnverted Resistivity Volume Fioure 25B lnverted Resistivity Volume E a E !o .zo'6otr G.9Lootr 75.O 60.0 45.O 30.o 20.0 15.0 10.0 7.50 5.@ 0- -0-0 -7 -O -14.0 -21-O 2s.0 t6_Z 8.3 i-ox -0-0 -7 -O -14.0 -'19.e Figure 26A Static Vertical SIices 32.0 Fioure 268 Static Vertica! Slices 16-z s-o E a EEo .14ootr Eo Lootr 75.O 60.o 45.0 30.o 20.o 15.0 10.o 7.fi s.00 ?5.016.7 8.3 0.0 x t Tl. -o9,iu€*i -0.0 -7 -A -1.+-0 GMMIR Profile Figure 274 lsovolume > 3000 oh "i# lsovolume > 3000 ohm-m Plan View -0.0 -7.0 -r4.0 2l,3B0 x 0.0 8.316.7a5.0 x Ftgure 27C lsovolume > 3000 ohm-m 750.00 500.00 350.00 2,5.OO 150.@ 100.00 75.00 60.00 /t5.00 30.00 20.00 1s.00 10.00 7.fi s.00 E a EEo .2o'6 otr (6o (,otr il *, :: .* a -21. 0.500 0.400 Distance in m. from beginning at W end E(9 E > = (E o o .z ct ou Fisure 28 - Gravitv Line G5 (c'I ol ol .=lJI >lTI elLI el orl6tl olLI =lol EI io o 3 o cD '= c.E, o -o Eol- E .; otr (E .9,o OOe! O I oO dI ooqo OO o oOc! O oo a?o oo u?o legru'r$;aelg a^llElau Bryant QonsuLAnts, lnc.' Dallas, TX LOG OF BORING B.1O Proposed lronbridge DeveloPment 410lronbridgeDtive (Lot 308 Rec Ceder) Glenwood Sprinss, Colorado 81601 Date Drilled : 1O192(x)5 'N = Standard Penelrd'on Test Ground Ehvation : Existing Grade 5= It odilied cone PeDetration Tesl CasingTo :Completion Drilling ltlelhod : ODEX Air RotarYBCt-ffi-.2n lronbn:doe Golf Club & il,lounbin Community Depth in f€6t 6ll E a, ooE Eg, 8.Fo CL Eoa, 6 oJ o g DESCRIPTION s C @ coo g o'6 E o CL E.9 E c) E.cl s E Jpa.gJ I .EJ 11o -go- a xo!,g o.::o -go- a j (h 8(\t{t IDcot,oo- a c ell =N IDc,6ID6q lr CL c.9o tn oo E oF eo j Eo ocorE =o- .oaot^gE EEo-ctr9 * o ;B EEDocoa,)o I EG o g2 6ll. o- 1- 2-. 3- 4- E- 6- 7- 8- o- 10: 11- 12- 13- 14- 15: 16- 17- 18- 19- a- 21- 2- n-. 24- %- %- 27- 8- B. 30- 31: 32- 33- u- 35- u x tx Moderate Yellovish Brovn, Pale Brown to Moderate Brorvn SILTY SAND with gravel (FILL). Ligtit Browr to Moderate Reddish Browrl SILTY SAND. Grayish Orange to Pale Yellorvish OrerEP SAND rrvith gravel and boulders. 6 d,tcL b d, Bc! !N Ao o a 6Io) EoE49o E N 3IIo,o,r Lighi Brom to Grayish OrangB SILTY SAND with feuy gravel. Dark Yellwyish Brown to Olive Gray CI-AY with silt. Boing Scheduh to and Tenninated at 30 Feet. Notei No seepagts water encounteted during ddlling. Bodrq remained dry and uncaved at cornpletion. Figure 30 LOG OF BORING B-11Bryant Bgil"ty+3its, I nc. l-t8clcglE clo FlsEl6.,llL , , Propoeed lronbridge DeveloPmem 410 lronMdgeDrive (Ld 311 Rec Center) Glentrvood Springs, Colondo 81601 kle Drill€d : 1ry19l2m5 'l\l = standaro Pen€rrarDn 16 GroundElevation:ExislingGradeoT=lVlodified.GonePenstralionT6l CmingTo :ComPldiott Ddlling trlethod : ODEXAirRotarYBCI-0E.277 tronOridoe Golf Club I Mqrntain Community Dedh in fo€il EE a !oog. Eo o.LF o.LEoo E oJ o E DESCRIPTION a cocooo oE = (, CL E.9g t=c)-o a EJ =)(r) s E J .9 io .eIL a xotE Fo tD -gr a jo 8(\tIt EDc6olUI a ceo =(I EDc6or!o- l! CL ce(,)U' oo 6 oF o j Eo ocoGEco- o6oE^ €FAEOEtrg 0-l {-l 2) 3-.1 4-.1 s-l 6-..J J+ 3- 9- 10- 11- 12- 13- 14- 15- ,6- 17- 18- 19-n- 2',1- 2.-n- 24- fi- 26-n-fr-E- 3p- 31- 32- 33-v- 35- 36- 37- 38- 39- 4- 41- 42- 4- 4- 45- 46- E x lsTl I [,loderate YellorYish Brovn, Pale Brqvn to Moderate Brown SILW SAND with gravel (FILL). Llght Brown to Moderate Reddish Brown SANDY SILT withdaY seams. Yellstiish Gray Small to Medlum Size GRAVEL with sand and bouldels. few gravd. lVloderate Brown to Light Brown SANDY CLAY (Mdd)with silt. I I I I I d Brl @ NFN s d ao Eoo6 Bo tsFN .Ao IoooItr oIN Brcvunlsh Grayto Ught Gny Medium to Large Well-Graded GRAVEL. Bodng Schedub to and Terminated at 40 Feet' Nde:. No seepage water encounteled durirE drilling. Boring'remained dry and uncaved at cornphtbn. F[ure 31 I I ! I ,z/.',,*\o Y,l' \a-*\ \.[_\ \-ffir cr\ Tent , \to ''-"-i '/,' ,r' ../' ,,r' {} '// NOHIH lnvestiootion Plon. Zone RBA+ Note: GMMIR Profile ond Boring Locotlons SCALE: 1"=60' 299 t I 306 R8A figure 3^ by SMA insp. lronbridoe Development 410 lronbridoe Dr Glenwood Springs, CORYANT 2033 Chenault Dr. Suite 150 Canollton, Texas 75001 Ph. (972) 713-9109 FAX (972) 71i9171 GMMIR Profile -0.0 .6.8 -13_5 Fiqure 33A lnverted Resistivity Volume g-3 x -,f*i -0 o-o o-o EI E !o |tt'-oo tr. Eo L C) -9 lJJ Fioure 338 lnverted Resistivity Volume 15-7 8.3 0-0 x 15O.r 100.r 75.O 60.o 45.O 30.o 20.o 15.O 10.o 7.50 5.00 s.7 -13-5 -?4.2 ?5.O GMMIR Profile Fioure 34A Static Vertical Slices -0.0 -6.8 ,Il|, E -2?fp\ 25-0 a: o.o/, 25-O t6.v 8-3 0-0 x Fioure 34B Static Vertical Slices 71- so-or/ . ' l:' ::,..::.:... . . / .t, ! EI Eso 't ..2ootr Eo L(,otr 2 15 10 75 60 45 30 N 15 10 7.! 5.( -0.0 -6.7 -13.5 -20-2 Y 2s-0 Fioure 358 lsovolume > 1000 ohm-m Plan View -0.0 6.8 -13.5 -?&-2 ?s_o o-0 83 16-7 e5-O x Fioure 35C lsovolume > 1000 ohm-m GMMIR Profile R8A Figure 35A lsovolume > 1000 oh 150 1 75.00 60.00 45.O0 30.00 20.00 15.00 10.00 7.fi 5.00 o.o *'', E a E Lo att'6 otr EC'.E o -c IJJ Y t. t. t ' ,: : , # : :t: alaa aa Zone RBA Rodor Anomolies Bw"otconarlhn8. hc RYANT 2033 Chenault Dr. Suite 150 Canollton, Texas 75001 Ph. (972) 713-910e Fn)( (972) 713-9171 ri aoI FNN Do od co E4oo E Bryant g3,?*yl|flts, rnc.LOG OF BORING 8-6 Proposed lronbridge Derrelopment 410 tronbrktge Drive (Lot 3{X} Rec Center) Glenwood Springs, Colorado 81@1 Date Drilled :10t18t206 'N = Standard PenetrationTeet Ground Eleralion : Exisling Grade *T= lttbd'died Cone Mralim Test Casing To : C,ompHion Drilling ltHhod : ODEX Air RotaryBCt{E.zn lronbrklge Golf Club & [rountain Community Dedh in ,€et oll E o oo E, '6o oo-Fg o- E rEa o oJ o !u DESCRIPTION a Eocoo g oE = & ,t EDe5 cf io a EJ E =E' J a .EJo oG o- a xoEE .9ofr I s jg, c,o(\:ll CDcoo G,o- a coo =N CDc6o(oo- lL CL c -9o o oo GoF lD j EC' ocoo- E6I o6oE^gE AEo-c lrJ {' IL Eo'te Bg E685)o s .Ed o oz lUlr. o- 1- 2- 3- 4- 5- 6- 7- 8- 9- 10- 11- 12- 13- 14- 15- 16- 17- 18- 19-n- 21- 2.- z3- 24-x-fr- 27- 8-n- 30- 31- 32- 33-g- 35- .ro- 37- 38- 39- 4- 41- 42- 43- 4- 45- $- u x E tvt Moderate Yellorish Brovn, Pale Brovn to Moderate Brovn SILTY SAND with sravel (FILL). Grayish Orange b Moderate Yelloryish Brown SILIY SAND wlth rredium size gravel and Cobbles (At de$h +7 bb cobbleB). Light Brown, Grayish Orangeto Moderale Yellowish Brown SILTY SAND with occasional gmvel. Oark Yellovrrbh Brown to Olive Gray CI-AY with sllt. Brwvnish Grayto Medium Light GrayWell-Graded GRAVEL wlth sand and rock. Boring Schedule to and Terminated at 40 Fed. Ndei No seepoge rvater encountered during drilling. Borirg remained dry and uncaved at completiofl. Figure 37 FNN d _.9LoooN o. o B .Y d d. 3o e NtsN!to tsdoIq E6Ioo FN ./}9 o troooN o- 6 8 + Bryant BSil;#r$its, rnc LOG OF BORING 8.7 Proposed lronbrirlge De\reloPment 410 lronbrktge Drive (Le[ 304 Ree Oenter) Glenwood Sprinss, Colorado 81601 He Drilled :1O|18f]Oc6 'tl = Standard Penefirat'pn Test c,rotrnd Elevation : Existing Grade {= llodilied cone Pe|retraiior Test Casing To : ComPleiion Drilling It dhod : ODEXAT RotatYscl{F.277 lronbrldoe Golf Club & Mountain Gommunlty Dopth in f€st 6ll E a) o0 E, '6 U' o.LF oE E6o E d,) o g DESCRIPTION I co Eo() E o'6 E c 8. -c.9 * Ef,.a a E Jpa.sJ a .EJ .9o6 d I xoT'E .9o -go- a to c!(t(\t*t CDcfrooo a co ll =N IDc tnooo- l.L CL co o =(t, oo6oF 6o $ Eo ocoo-tco- ! .=ofroE^.eF 15EOEtr9 ci Eote;8PYE:tctDocoo )o I _gd o E =oll o- 1- 3- 4- 5- 6- 7- 8- 9- 10- 1t- 12- 13- 14- 15: t6- 17- t8: 19- 20- 21- D.- z3- 24-. z5- 26- 27- 28- B. 30- 31: 32-. 33- v- 35- x x tx Modente Yellowish Brotm, Pale Brown to trloderate Brorvn SILW SAND wittt snvel (FILL). Yellovish Grayto Grayish Orange Small to Large size GRAVELwith sand. Pale Yellorrbh Orange to Light Brovrn SANDY SILT. Boring Schedule to and Termlnatd d 30 Feet. Notei No seepage water encounteted dudng drilllng. Borlng remained dry and uncaved at compldion. Ftgure 3E oa c 6 Fqoo o? d! FNd s o Inoo a 6ooq Bryant B3il;,yt+Tts, I nc LOG OF BORING B.8 Proposed lronbridge DeveloPment 410 lronbridge Dlive (L€[ 3m Rec Centar) Glenwood SPnngs, Cdotrdo ll601- Oae Orilted :1o19l2oi}S 'N = Standard Penotraiion Test Ground Elo\Etion : Exiding Grade oT= l'lodi$€doonB MisnTed Casing To : ComPldion D,illing nbthod : ODD(Air Rotary L t^i lar lvrel c !9ls iEIE:-= I c,o I tL BCt{E.m lronbridse Gdf Club & Mountain CoErnqlL Depth in f6et I E CI'vooE 5o o CL F -co. EG at) o oJ o g DESCRIPTION a cocoo E =o'6 = 8_ -c-9E cl ao s EJ Il'5 -gJ a .EJ .9o(oo a xo,t =q o=o.!o t joo Rtl CDc -oo(o.L a co L =ol EDc,Eooo- l! CL co () =o oU' EoF t j Eo ocoLEcoI >! o6oE^oE EEo-cfi9 o-.i ..1 t-t .J 2).l 3-..1 .,] 41 o- 7- 8- 9- 10: 11- 12- 13- 14- 15: 16- 17- 1E: 19: n- 21-. 2.-. B-. 24-. %- %- 27- 28- B: 30- 31- 32- 33- u- 35- I x x tvl Moderate YellqMs,h Brown, Pale Brown tio Moderate Brfln SILTY SAND with gravel (FILL). Light Brovtt to ttloderate Reddbh Brwvn SlLry SAND with gravd. Gnayish Orangeto ModeEte Brown Well-Graded SILTYSAND. Brovynish Gray to Light Gray Small to lvledium Size GRAVEL with t lt. Bodng Schedub to and Terminated at 30 Fe€t. Ncftei No seepge water encour*ered during drillirg. Borlng remained dry and uncaved at completidl. Fbure 39 o!6 6E.L d. Bo e tsts do q 6 ts ctI cLDooN ao3 + Bryant Bsilrt11l[3its, Inc.LOG OF BORING B.9 Propoced lronbridge DeveloPment 410 konbddgre Drive (Lc{307 Rec Center) Glenvvood Sprinss. Colorado 81601 Date Drilled : 1U19r2O(E 'N = Standard PerHletion T66t Ground Elevalion : Eristing Grade *fe l$odilied corte Feoetratbn Test Casing To : Compldion Drilling [,lethod : ODEXA|T RotaryBCt4Ezn lronbridoe Gotf Club & Mountain Community Dsdh in fed o -ct o .YooE 5o o CLFg CL E6o E _9 {, g DESCRIPTION a co Eoo Eao6 = & s .9)g c).ct s .EJ I)tr = s EJ(, oo o- a xot,c .9o -aG a jg, ooGItt CDtrBo6G I cog =c{ EDc,6lt6o- lt-IL co o (o oo 6oF a j E eocoo-t,co- :a=2o IDoE,^oF .,Eo.ctr.9 d E $e€€TEDocoo )iD a Eo U'o =6IL o- 1- 2-. 3- 4- 5- b- 7) 8- 9- 10- 11- 12- t3- 14- 15: t6: 17 -. 18- 19- 20- 21- 2) B-. 24- %- 2t5- 27- 28- n- 30- 31- g2- 33- u: 35- u x tx i/loderate Yellowish Brovn, Pale Brown to ilbderate Brown SILTY SAND with sravel (FILL). Light Broryn to Moderate Reddish BroMl SILTY SANDwith grarcl. Dark Yelhrvbh Brwrm to Olive Gny SILTY CLAY rvih sand. Pale Yelknbh Orange to Gmyish Orange SILTY SAND wih grarrel. Moderate Brovrn to Light Brown CLAYEY SILT with sard. Bodng Schedub to ard Terminated at 30 Feet. Nctei No seepage water encountered during drilling. Borlng remained dry and uncaved at compHlon. Figure.lO Note: OIMIR Profile ond Boring Locotions orE SCALE: 1":60' BryentCqlerlhrila ha RYANT 203i! Chenault Dr. Suite 150 Canollton, Texas 75001 Ph. (972) 71&9109 FN( (972) 7'.t}g',t7'.| lronbridoe Development 410 lronbridoe Dr Glenwood Springs, CO figure 41 by -SldA- insp. Figure 42A lnverted Resistivity Volume Figure 428 lnverted Resistivity Volume EI E-co .9.oo G, (6o o -9 UJ 75.O 60.o 45.O 30.o 20.0 15.0 10.o 7.50 5.OO 0-0-o-0' -7.4 -14.0 18-Qe6-00-o x -?1.0 Figure 43A Static Vertical Slices -0-0 -7.0 -1+-0 -21.0 9s_9 -7-0 Z -14.0 -21-0 o.oo-o 6-D Ieo x Figure 43B Static Vertical Slices 2 15 1 75.00 @.00 45.00 30.00 20.00 15.00 10.00 7.fi 5.00 Et EEo .9. atotr E C) C)otr "8'd L8-Oa06.0 0-0 x Figure 44B lsovolume > 1000 ohm-m Plan View Fioure 44A lsovolume > 1000 oh 1 1 75.00 60.00 45.00 30.@ 20.00 15.00 10.00 7.50 5.00 -0-0 -7 -O -14-0 ''bg E a E !o .= .t2ootr Eo Lootr Y 0-6-o2_B_0 x Fiqure 44C lsovolume > 1000 ohm-m {.0 -7.0 -1,+.0 -21-0 Distance in m. from beginning at SSW end (u (9 E *'t (E (, o G o N, 0.06 0.05 0.04 0.03 0.02 0.01 0 -0.01 iil:riliiriiffill:r::l1,ii; :r':., .t:rljt.aii i ii,;:1lliff rii..lti|i:iit, ill;i!r:i ,liiini;iliilii-iiijil ...,. ..4ffi..,-'ffi iiffitiii:lffiffiiitiiiiiiill li[tlii{ffiliri;ilnr,,,#iri,'il l$irt*rffitriritffi lf;,ufr$it{ffi*ffi i-r, :i)iair:;.'::,r". ra:l,l ."itif,lt:iii;liiri i'ii,r',:,'$iill ';..ir,r.. liirfl!-rir,d ;;ltrii,:.:l rlii iilJi:i.,.i irr$iiil*$$ iri ', 'iiiii,lliii,ilii;',ir.rrilj;it.,.:.l:.ra'I: t ir.".r,;r.rir. il r' I r,'j, :li.':r l ,^i. 'l :.llr:rl tri i...,lirll.'r .",-'"""'-- -'lfrl,.l .i iii r':,riitj:i. ::.rr;.r. I i.r,rl',.i..:l;:,t,,.:.W*lirii iil'ilirrl;-i .li l rr,]::1i l I Utlr ,..trt.l.t ir: irolil,'i i \ .'). i ' 1.,' . i. \:"-'t i',:.,,' :'{$;|i"t r,i'liir:i;:;:r t,n;t)iii;,ir;i,,r; W, tt i :.",,",'.,', ,. ' .,..]J i, :iiitiii .ii,triirj:t i: iiilCI $$iftiffifj;tr:1i: i:. ri.r;r ir':. ia _. ; lliiii...!: iviil:it ji,lii : lllrr '', rr)i, 'l,l.i0;ri-i, . ,,1' $fli1firytri ,]iiii:$ii ,.i'1i.rl:::i!: l::r.1,,iii: itr. I :r .:; iijr.. , ,r:r ,.i, t-, ":iljriiirit ill:il-ir., ri:.i.:;irii|,li:.,i1 .:,.:, :.i...: .r1' .r.r. ji,i .-r.,. lir:, :irlil:i , r'' ii, il, ..i r:l: l- ..'I,,iir;rlliliiililitll i(l r':r':.rr, !n , i.,..ir lilLl ii ::rr iil:iri.l i ':iti:j ti1.i...i:i.r :. :rl,il I '',,,i:ii :;.i t, ,,ri :ia,jl$r;i:i'r;l,i;::,; il$iffi tlii: ' l. :'.r:. 1:.:.i....: ,:-,:ir^t", . '^1 .,,-r., -; : 1'l r;'"' ' . ., ir. .'.1-.;'.,,] ,, , -0.02 -0.03 -0.04 Figure 46 - Gravitv Line G4 o IFtsI N d tstsN ul9 o=u-o 8I a. a {+5 Brya nt B!il,',y+Bits, rnc LOG OF BORING A.2 Proposed lronbridge DeveloPment 410 tronbridge Drive Glenvrood Springs, Colorado 81@1 Daie &illed :9l14l2cxJr' 'N = S-tandard Penelratbn Tosl Ground Eleration : Existing Grade. 'T= lJHilied cone PeoeMion Test C*ingTo : M Drilling }lethod : Cont. Flighl Alg€rBCI-06-Zri lronbridoe Golf Club I Mountain Community Dedh in f€d olt E, at, .v,ootr '6 (n o.L F -eo Eo ao E oJ C' g DESCRIPTION a coco() g,o'6 = & -cg g cf bo a EJp -gJ * E J .9 itso- a xotE .9o -gq s to c,c)(\I:lt EDEoooo- a co o =ol EDc6ooo- tL CL co E (r, oo EoF eo j Eo ocoo-EcoI .>IooE^ 8F6Eo.rtrg 4Eo 3E EEDocoo )rt a E6 o Eeolr o: 1- : 2-. :3- : 4: :tl :u: :,: ': ,l 10i : ,rl : 12-,. ,tl ,o-.. ,ul ttj : 17-. : ,t, :,,: :n- Ligtrt Brorn to lttloderate Brown Po,vdery SAND with small size gravel. [,loderate Reddirh Brown to Light Brown SAND with light brovn clay seams. BorirE Termfded at t7 Feet Dueto Cdble-Stone. Note:- No seepage water encounteled during drllling. Bodng remained dry and caved at compe{ion. F:lg,urc47 E t ri 3oI F ,Ao dd NtsN s -9tr Bryant Qonsu[apts, lnc.' Dallas, TX LOG OF BORING B-2 Proposed lronbridge Development 410 lronbrklge Drive (Rec Center) Glenurood Sprinos. Colorado 81 601 Dale Drilled :1Ol17t2OG *N = Standard Penetratioo T6l Ground'Elevalion : Existing Grade 'T= lJlodilied Coae P€Detration Tes Casing To : Completion Ekilling lt/ldhod : ODEXAIT RotaryBCtoE.Zn lronbridoe Gdf Club & MouEtain Communitv Deptrt in fd IE ottootr '6a oo-Fo .L Eo CI' o oJ o E DESCRIPTION a coEoo E o6 = & g -9g cf bo I E Jp:,-gJ I E J llo lUc a x(,1'E o,Ea -go- * j @ooGI:lE EDc.'6 a lUG a coo =ot IDc6ol!o- tL CL co Eo oo GoF eo j EIocoLt lUI .>o6ot^ €F6EOEtr9 o. Eo 3A CCDocoo, ) al, s E6 a, e =olL o- 1-. z- 3- 4- E_ 6- 7- 6- 9- t0- 11- 12- 13- 14- 15. t6- 17 18- 19- N: 21- 2- n- 24- %- 26: n- 5- N- 30- 3't - s2- a2) -l 34--.1) 3s--l tx Moderate Ydl@,ish Brovn, Pale Brour to Moderate Brown SILTY SAND with gnvel (FILL). 6 3 8.2 Light Brwvn to lt oderate Broum SILTY SAND. Yellowish Gray lvledium to Small Size GRAVEL with lght brown end (Very Dry). Pale Brown, Moderate Brom to illoderate Yellowbh Brom SILW SAND with gravel Brevnish Gray to Pale Brovn Small to Medium Size Wdl-Gratu GMVEL. Boring Schedule to and Terminated at 30 Feet. Ndei No seepage water encountered during ddllirp. Boirp remained dry and uncaved at completion. Figure 4E 6ooN o- @ BIq ooiioocL 6 I sN g fo co Eoo5 ofoqIIcs Bryant BS,?#lBits, lnc.LOG OF BORING B-4 Proposed lronbridge DeveloPment 410 honbridgre Drive (Propoeed Rec eenter) Ghnu,ood Sprims, Colorado E1@1 Daie Drilled : 1O182O(E 'N = Standard P€nalratbn T€sl Ground Eloation : Eriding Grade 5= illlodilied cone PeB€tration T66i Casing To : ComPletion Drilling ltr/lettrod : ODEXAiT RotaryBCL06.zn lronbridoe Golf Club I Mwnhin Community Dedh in f6ot Elt E aD oo E. oo o, CLF -clL ElEo o oJ o g DESCRIPTION a c o,coo g o'6 = e & -cC" g c) bo a E Jpac,J I E J .9o G o- s xoE .E oEo .E(L a j (r, 8NIt CDc'inooIL I co o =ot CDcolD rEo- l! CL c.eoJa oU' Go o j EIoc,oL!tc6I booG.^ €FUE6,Eul {, o Eo 3eov EEDocoo )it a E6 o Ea ol! 0- 1-. 2-. 3- 4- 5- o- 7- 8- 9- 1o: 11- 12- 13- 14- 15: 16: 17 -. 1E- l9- N: 21- D,- n-. 24- x- %- 27- 2A- E- 30- 3t- 32- 33- g- 35- x x tx illoderate Yellowish Brou,n, Pale Brorvn to Moderate Brorn SILW SAND wlth orartel flLL). 10 23 1 12..9 ffierate Brcnyn SILTY SAND with chyseams and gravel (At dedh lG11'chy). Brownish Gnyto Pale Brown Medlum to Large Size Well-Graded GRAVEL with sand. Large Boulders from 21 to 23 fed Large Borlders frofiiz4lo27 td Boring Sciedub to and Terminated at 30 Fe€[. Notei No seepage water encounteted during drilling. Borlng remained dry and uncaved at €ofliphtion. Figure 49 FNN s o LoooN oI R+ !; )8 /t 306 ,iilIii!tittit!t i,'/,// /' ,/,/i fri NOHIH /1^\. {{ F\\tu\\ i.GEf Cri 1 Tent lnvestigotion Plon. Zone R10 Nots GMMIR Profile ond Boring Locotions orc SCALE: 1":60' 31 6 lronbridqe Development 410 lronbridqe Dr Glenwood Springs, C0 figure 50 by SMA insp. BryantCffiuffiih, RYANT 2033 Chenault Dr. Suite 150 Canollton, Texas 75@1 Ph. (972) 713-9109 FA|)( (972) 71U9171 -20.24 69_9 {.0 s.8 -13.5 46.6 Y Figure 51A I nverted Resistivity Volume Figure 51B lnverted Resistivity Volume 150. 100. 75.0 60.0 45.0 30.0 20.o 15.O 10.0 7.50 s.00 E a E.go 't aD'-o o tr. (Uo L(, (D LU 0- -0-0 -6.8 -13-5 -20.2 30-0 -0.0 -6.8 -13.5 -zgf ; Figure 52A Static Vertical Slices Figure 52B Static Vertical Slices EI EEo o'-o o E, (6 .9L c)otr Y 46. 150. 100. 75.0 60.0 45.0 30.0 n.o 15.O 10.0 7.50 5.00 .o.B' -6.7 -13.5 1.0.0 o.o -20.2 20.0 x 30.0 46.6 Y o.oo.o Figure 53B lsovolume > 1000 ohm-m Plan View 10.0 x 0.0 10.0 20.0 30.0 x Figure 53C lsovolume > 1000 ohm-m GMMIR P Figure 53A lsovolume > 1000 oh -m 35 2 15 1 75.00 60.00 45.00 30.00 20.00 15.OO 10.00 7.fi 5.OO -0.0 -6.8 -13.5 '29f 6 15 10 75 Y EI EEo a'-oo tr. 6 C) (t -g UJ 't .* ?; *#** -0.0 -6.8 -13.5 -2W. o,oo.o Figure 54B lsovolume > 3000 ohm-m Plan View Fioure 54A lsovolume > 3000 69.9 46.6 23.3 z I EI EEo '= at'6 otr (Eo (, -!PuJ 0.0 75.00 60.00 45.00 30.00 20.00 15.00 10.00 7.50 s.00 0.0 10.0 20.0 30.( x Figure 54C lsovolume > 3000 ohm-m 10.0 20.0 E(, E >.= (E o o sou 0.200 0.150 0.100 0.050 0.000 -0.0s0 -0.100 -0.150 -0.200 Distance in m. from beginning at SSE end Fiqure 55 - Gravitv Line G7 Bryant ggil*yl$its, |nc LOG OF BORING B-5 Proposed lronbridge Development 410 konbridge [lr$rl€ (Lot 298) Gbnwood Springs, Colorado 81601 Date Drilled :.1OI18DA6 'N = Standard PenetratlonTest Grourd Etenation : Eristing G,rade *T'lvlodilied Cone Penerffiion Tat Casing To : Compldkm Drilling ilElhod : ODEX Air RolaryBcl{rzn lronb,ridoe Golf Club & Mountain Cornmunitv ryh in fest E3E at, .Yootr '6 (r, oo. F oE Eoo 6 oJ o g DESCRIPTION a Eocooo =o'6 = 8. CD g c,l o a .EJp =cr J * .EJ o o -(Uo- * xoi, -EE .9o .Eo- t j th oI:ll C"c6ol!o_ a Eoo =6l CDc6ooI TLe coI3o oo G C'F co j Eo ocoo-pco- 2 ldaoE^9E6Eo.gtr9 CL Eo 3Eov CCDotoo)o a -so o oz Gl! o- 1- 2- 3- 4- E- 6- 7- E- 9- 10- 11- 12- 13- 14- l5- 16- 17- 18- 19-n- 21- 2,-B- 24- %-a-T- xr- B- 30- 31- g2- 33-v- 35- 36- 37- 38- 39- 40- 41- 42- 43- 4- $- 46- x x tvl Modenate Ydlqvish Brorrn, Pale Brovvn to Moderate Brown SILTY SAND with gravel (FILL). 5 1 7 1 129.9 81.6 Gnayish Orange to Moderate Yellotlsh Brcnrn SILW SANDwith gnvel. t .i 3o ao tsNNg (r dl tsNcrI I iE 6II d' 6 B Moderate Brovn to Pale Brryn liedium to Large Size GRAVEL. Grayish Orarge to Moderate Yellotrybh Brown SANDY SILT. Brownish Grayto Medium Light GrayWell-Graded GRAVEL. Bodng Scfredub to and Terminated et 40 Feet. Ndei No seepage nater encountercd durlng ddlllng. Boring remained dry and uncaved at compl€tion. Flgure 56 E 6 d a6 @ tsNN do o d F N lA9 o LoooN o- .o I I + Bryant $3,?rrrY tBits, I nc.LOG OF BORING B-13 ProPosed lronbridge Dertelopmenl 410 konbridgp Drine (Ld 300 Rec Center) Glerrwood SPrings, Colonado El@1 He Drill€d :1Or]OI2cf6 'N = Slandard Penstret!'n T€51 Ground Elenraiion : Existing Grade 'T= It/lodilied cone Peoetration Ted CasingTo :ComPHion Ddlling illEthod : ODEXAIT R&tYBCt+5-277 lronMdoe Golf Club & Mountain Comrnuntty Deilh in t6d EIl E o .yooE Ea, oo-Fo CL E6U' o oJ o g DESCRIPTION a co Eooo o6 = 8. .g -9g cfao a E J =).gJ I EJ o o -ctL I xo1'E .9a .Eo- f j U' oo(\t:ll EDc,6 IDoo- a goo =C.l IDc'in 0Go- L CL co E =o oo GoF l0 j Eo ocoo.tc rEI .> -u6oG.^ €F6Eo-ctr9 + 5)6,8- =t =a5c)o )a a E6 aD g =o LL 6- 7 8- 9- 10- 11- 12- 13- 14- 15: 16: 17 -. 18- 19- n- 21- 2- B-. 24-. %-. fr-. 27- %- B- 30- 31 . 32- 3rit- 34- 35- x tx Irroderate Yellovtsh Brovwt, Pab Brown to Moderate Brown SILTY SAND with sravel (FILL). - Yetlorrish Gray to Grayish Orange Small to Medium Size GRAVEL with sand and boulders. Light Brorn, tt oderate Bromt to tttloderate Yellorlslr Brovm SANDY SILTY CI-AYwith fetv gnvel. Dark Ydlwvish Brown to Olive Gray Moist CLAY. Borlng Sclreduh to and Terminated at 30 Fect. Ndei No seepage rvater encountered durirq dritling. Boring remained dry and uncaved at cornple[ion. F(rure 57