Volume 2. Geotechnical Evaluation for FINGER LAKES STORAGE BRINE POND. February 25, Prepared for:

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1 February 25, 2011 Volume 2 Geotechnical Evaluation for FINGER LAKES STORAGE BRINE POND Prepared for: Mr. Michael LaRose Finger Lakes Storage, LLC 111 North Franklin Street Watkins Glen, New York Prepared by: C.T. MALE ASSOCIATES, P.C. 50 Century Hill Drive Latham, New York (518) FAX (518) C.T. Male Project No.: Unauthorized alteration or addition to this Copyright 2011 document is a violation of Section 7209 C.T. MALE ASSOCIATES, P.C. Subdivision 2 of the New York State Education Law.

2 Geotechnical Evaluation Finger Lakes Storage Brine Pond Reading, New York TABLE OF CONTENTS Page 1.0 INTRODUCTION PROJECT DESCRIPTION Site Description Brine Pond Description SUBSURFACE INVESTIGATION PROGRAM Test Borings Test Pits Groundwater Monitoring Wells Slug Testing Laboratory Testing SUBSURFACE CONDITIONS Overburden Bedrock Groundwater STABILITY ANALYSIS ANALYSIS & RECOMMENDATIONS Drainage Course Analysis Slope Stability Analysis Design Recommendations Construction Recommendations CONSTRUCTION MONITORING CLOSURE...12 TABLES Table 1: Required Factors of Safety... 7 Table 2: Computed Factors of Safety i

3 TABLE OF CONTENTS (cont.) APPENDICES APPENDIX A: APPENDIX B: APPENDIX C: APPENDIX D: APPENDIX E: APPENDIX F: APPENDIX G: APPENDIX H: APPENDIX I: Subsurface Investigation Plan & Profiles Subsurface Exploration Logs Test Pit Logs Groundwater Monitoring Well Construction Logs Slug Test Results Laboratory Test Results Reference Materials USGS Interactive Deaggregation Graph Slope Stability Results i

4 C. T. MALE ASSOCIATES, P.C. 1.0 INTRODUCTION This report presents the findings of an investigation and geotechnical evaluation of the subsurface conditions present at a site in the Town of Reading, New York proposed for the construction of a surface impoundment for a brine solution. The project site s subsurface conditions have been investigated through the advancement of test borings, excavation of test pits, installation of groundwater monitoring wells and the performance of field and laboratory tests. From our evaluation of the conditions disclosed by this investigation, we have developed recommendations for the design and construction of the proposed impoundment and evaluated the stability of its embankment side slopes. This investigation has been performed at the request and authorization of Mr. Michael LaRose of Finger Lakes Storage, LLC. 2.0 PROJECT DESCRIPTION 2.1 Site Description The project site is located immediately east (downhill) of the intersection of New York State Routes 14 and 14A in the Town of Reading, New York. The Village of Watkins Glen is located approximately 3 miles to the southeast and the Town of Reading approximately 1.5 miles west (uphill) of the site. Currently the site is an undeveloped area with significant vegetative growth across much of its surface. The existing ground surface of the area proposed for the surface impoundment slopes downward to the east at an average inclination of 6 to 8 percent. Less than ½-mile downhill (east) of the site is Seneca Lake. 2.2 Brine Pond Description Brine solution will be removed from subsurface caverns to develop storage volume for liquid petroleum gas. The brine solution removed from these caverns will be temporarily stored in an impoundment with a holding capacity of approximately 2.1 million barrels (88.2 million gallons). With the site s sloping ground surface, the impoundment will be created by excavating into the existing grade on the pond s uphill side and constructing an embankment on its downhill side. Up to 25 feet of cut and 35 feet of fill will be required to construct the impoundment. The embankment constructed on the downhill (east) side of the brine pond will have a top elevation of feet. Where the site is lowest in elevation, the toe of this embankment will meet the existing site grades at elevation 790 feet, resulting in a maximum embankment height of 51 feet. 1

5 C. T. MALE ASSOCIATES, P.C. On the embankment s interior, its side slopes will be inclined at and between 1:4 and 1:3 (Vertical: Horizontal). Along the impoundment s west side, its interior slope will be inclined 1:4. Opposite this slope, the embankment s interior slope will be inclined 1:3 (V:H). Between the east and west sides of the impoundment, the embankment s interior side slopes will gradually transition between these inclinations of 1:4 and 1:3. The exterior slope of the embankment facing Seneca Lake will be graded at 1:4 to help balance the earthwork involved in the pond s construction and, in doing so, enhance its stability. A perimeter access road will be constructed around the top of the brine pond. The road will be surfaced with compacted crusher-run stone. It will be approximately 12 feet wide and be accessed via a grass paver drive that connects to a gravel drive present along the east side of the impoundment. The impoundment will be lined to contain the brine solution. The liner system will be composed of two (2) geomembranes, consisting of an upper 45-mil reinforced polypropylene liner and a 60-mil textured HDPE geomembrane for the lower with a geonet leak detection drainage layer between them. 3.0 SUBSURFACE INVESTIGATION PROGRAM The subsurface conditions at the site proposed for the brine pond s construction were investigated in two (2) phases. The first was performed to provide an overall characterization of the overburden and groundwater conditions present and to determine the type of bedrock and its depth below grade. For the initial investigation, six (6) test borings were advanced and, at four (4) of these locations, groundwater monitoring wells installed. The second phase of the subsurface investigation program was conducted to further define the overburden profile, bedrock elevations and groundwater conditions. It included the advancement of ten (10) additional test borings, installation of four (4) more groundwater monitoring wells, excavation of nine (9) test pits and the performance of additional field and laboratory tests. The field testing involved the performance of several slug tests to evaluate the permeability of the overburden and weathered/broken bedrock found to directly underlie the same. 3.1 Test Borings All test borings were advanced by SJB Services, Inc. The initial test boring program was performed between October 1 and October 8, 2009 and the second program between October 11 and October 20, The test boring locations are shown on the Subsurface Investigation Plan presented in Appendix A. Those advanced in the initial program are labeled as SB-1 through SB-6 and those advanced in the second program as SB-7 2

6 C. T. MALE ASSOCIATES, P.C. through SB-16. The locations shown on this plan were established through GPS methods. A Central Mine Equipment Model 850 track-mounted drill rig was used to advance all of the test borings. They were advanced and cased against collapse through rotary drilling of 3-¼ or 4-¼ inch inside diameter hollow stem augers. As the augers were advanced, the overburden was sampled and its penetration resistance determined in accordance with the procedures of ASTM Designation D-1586, Standard Method for Penetration Testing and Split-Barrel Sampling of Soils. In general, in areas where existing grades will be lowered to construct the impoundment, sampling and penetration resistance testing was conducted in successive two (2) foot intervals through the proposed depth of cut and then at intervals of five (5) feet or less until refusal of the augers to further penetration was encountered. In areas requiring fill placement, sampling and penetration resistance testing was initiated at the ground surface and conducted at intervals of five (5) feet or less. At four (4) of the test boring locations, the nature of auger refusal was investigated through rock coring methods. This work was performed following the procedures of ASTM Designation D- 2113, Standard Practice for Diamond Core Drilling for Site Investigations. Rock coring was initiated at the depth of refusal and terminated after one or two runs, resulting in 3 to 10 feet of penetration into sound bedrock. A representative of C.T. Male monitored the test borings, recorded the standard penetration resistances, field classified the recovered soil and rock core samples, and placed representative portions of the soil samples in jars and the rock cores in wooden core boxes. These samples were brought to our office, examined and classified by a geotechnical engineer. A Subsurface Exploration Log was prepared for each test boring to present these classifications and the records maintained in the field during their advancement. They are presented in Appendix B along with a sheet and key that explains the terms and symbols used in their preparation. 3.2 Test Pits To supplement the subsurface data gathered by the test borings and collect bulk samples for laboratory testing, nine (9) test pits were excavated at various locations around the proposed pond site. The test pits were excavated by Finger Lakes Storage, LLC on October 21, and October 22, 2010 using a Caterpillar 315C track-mounted excavator. Their locations, as established through handheld GPS methods, are shown on the Subsurface Investigation Plan in Appendix A. A geotechnical engineer from our office monitored the test pit excavations, classified the soil types encountered at each location and noted the presence and depth at which groundwater was encountered. A Test Pit Log was prepared for each excavation to 3

7 C. T. MALE ASSOCIATES, P.C. present these classifications and the records maintained in the field. The test pit logs are presented in Appendix C. 3.3 Groundwater Monitoring Wells A total of eleven (11) groundwater monitoring wells were installed at the site. The wells were constructed using two (2) inch diameter Schedule 40 PVC pipe, the bottom 5 or 10 feet of which was machine-slotted. The annular space between the augers and well screen was backfilled with Filpro Industrial Quartz Sand from 6 inches to 2 feet above the top of the well screen. A bentonite seal approximately 2 feet thick was placed above the screen s filter sand. Above this seal, native soils (auger cuttings) were used to backfill the annular space between the PVC riser pipe and the drill holes. At the test boring locations, water could be heard entering the drill holes once the augers fully penetrated the overburden and were extended into the underlying layer of weathered/broken bedrock. Above these depths, seepage of water into the drill holes was not audible. At several of the groundwater monitoring well locations, a well couplet was installed to determine if a hydrostatic difference was present between the weathered/broken bedrock and the sequence of glacial till found to directly overlie the same. At these locations, one (1) well was installed across the weathered/broken bedrock and glacial till interface while an adjacent well (suffixed with the designation A ) was installed solely within the glacial till. A Groundwater Monitoring Well Construction Log for each of the wells installed at the site is included in Appendix D. 3.4 Slug Testing Slug testing, performed to assess the permeability of the overburden/weathered bedrock, was conducted at eight (8) of the monitoring well locations. Two (2) of these tests were performed in wells screened only within the glacial till. The other tests were performed in wells screened across the interface of the glacial till and underlying zone of weathered/broken bedrock. Pressure transducers were placed near the base of the wells to avoid contact with the slug. Data collected by the transducers during the performance of these tests were transmitted directly to a laptop computer and, upon inputting the well parameters, the data was analyzed with the assistance of the computer program AQTESOLV, Version Permeability values were typically computed using the rising head data and the KGS Model, as developed by Hyder et al. (1994). Permeability values for the glacial till were found to range from 1.3x10-6 to 7.0x10-6 centimeters per second (cm/s) while the composite permeability values of the weathered rock/glacial till interface were found to range from 1.2x10-4 to 1.3x10-2 4

8 C. T. MALE ASSOCIATES, P.C. centimeters per second (cm/s). Example output from several of the computer analyses are contained in Appendix E of this report (Volume 2). 3.5 Laboratory Testing Laboratory testing of the bulk samples collected from the test pit excavations was conducted in our laboratory to determine the samples optimum moisture-maximum density relationship, water content and grain size distribution. This testing was performed in accordance with the following ASTM procedures: ASTM D-422: "Standard Test Method for Particle-Size Analysis of Soils". ASTM D-1557: Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Modified Effort. ASTM D-2216: "Standard Test Method for Laboratory Determination of Water (Moisture) Content of Soil, Rock and Soil-Aggregate Mixtures". Appendix F contains the results of the laboratory testing. 4.0 SUBSURFACE CONDITIONS 4.1 Overburden Approximately 2 to 10 inches of topsoil was encountered across the site and found to be underlain by a deposit of silt 3 to 9 feet in thickness. The silt deposit contained little to near equal amounts of clay, trace amounts of fine sand, and occasional cobbles. The number of cobbles and the amount of sand present within the deposit was found to typically increase with depth. Standard penetration testing (N-values) within the silt ranged from 6 to 27, indicating it is of a medium stiff to hard consistency. A thin sequence of sand and silt was encountered directly beneath the silt deposit at six (6) of the explored locations. At these locations, the sequence was found to have a thickness of less than 5 feet and to be of a compact to very compact relative density, with N-values ranging from 38 to 64. Found beneath the sequence of sand and silt, or the silt deposit where the former was not present, was glacial till. Embedded within the till s fine sand/silt soil matrix was medium to coarse sand and fine to coarse gravel. Numerous cobbles and boulders were also found to be present as evidenced by the difficulty in advancing the test borings with depth as well as their presence in many of the test pit excavations. N-values within this deposit ranged from 25 to more than 100. The test borings penetrated the deposit at depths ranging from 16.5 to 33 feet prior to encountering weathered bedrock. 5

9 C. T. MALE ASSOCIATES, P.C. Profiles of the subsurface conditions encountered at the site are presented in Appendix A. The lines along which they were developed are shown on the Subsurface Investigation Plan also included in Appendix A. 4.2 Bedrock Bedrock at the site was found to be composed of interbedded shale and sandstone. The bedrock was found to be medium hard and contain numerous fractures with intermittent soil seams. It was found to be thinly bedded at or near a horizontal orientation. Rock Quality Designations (RQD) of the recovered core ranged from 0 percent to 77.8 percent. 4.3 Groundwater Groundwater levels in each of the monitoring wells were measured on several dates. The most recent observations were made on January 11, 2011; more than one month after slug testing was performed in several of the wells. On this date, the observed groundwater levels were considered to have stabilized and were found to be present 1.3 feet to 6.2 feet below the existing site grades. At one monitoring well, MW-16, a strong sulfurous odor was noted to be present during construction of the well. This odor was not noted during follow up observations. Water was observed weeping into the test pit excavations through granular seams or partings within the overburden at depths ranging from 4 feet to 10 feet beneath the ground surface. At the test boring locations, water could be heard entering the auger casing once the augers fully penetrated the glacial till and were extended into the underlying layer of weathered/broken bedrock. Above these depths, seepage of water into the drill holes was not audible. The water levels in wells screened across the glacial till/weathered rock interface were typically within 6 to 12 inches of the levels observed in wells of the same couplet which were screened only in the overlying glacial till. Collectively these observations indicate that groundwater is contained in the layer of broken/weathered rock and confined by the overlying till which has a permeability 2 to 4 orders of magnitude less than that of the layer of broken/weathered rock. Groundwater is also contained within granular seams of the overburden which, at some locations, is perched above the piezometric surface of the confined groundwater table. Appendix A contains a Groundwater Contour Plan, Drawing SI-4, which was developed using the most recent groundwater level observations. The elevation of the groundwater table is expected to vary on a seasonal basis. Additional groundwater level observations will be made to further define its potential fluctuations. 6

10 C. T. MALE ASSOCIATES, P.C. 5.0 STABILITY ANALYSIS Although the impoundment s embankment does not fall under the classification of a dam, the stability of its side slopes was analyzed following procedures identified in the DEC publication Guidelines for Design of Dams. These guidelines reference the use of methods of analyses outlined in the U.S. Army Corps of Engineers (Corps) publication EM , Slope Stability. Seven (7) load cases are listed in the USACE publication as being applicable to new earth and rock-fill dams. As the Finger Lakes Storage Brine Pond does not have a spillway, only four (4) of the load cases were deemed to be applicable to this project. A description of each of the loading conditions, the slopes analyzed, and the minimum required factors of safety are shown in Table 1 below. Table 1 Required Factors of Safety Case No. Loading Condition Pool Elevation I End-of-Construction II Long-Term with Steady Seepage and Maximum Storage Pool (including Design Rainfall Event) Slope Requiring Analysis Inside & Outside Required Factor of Safety Outside 1.5 IV Rapid Drawdown Inside 1.3 VII Earthquake Case II with Seismic Loading As Noted Above Inside & Outside The stability of the embankments was analyzed using the computer program GEOSLOPE, Version 5.0. As noted in the aforementioned Corps publication, soil properties for the embankment at End-of-Construction are based upon a total stress analysis using undrained strength parameters. For the remaining load cases, long-term ( drained ) strength parameters were utilized in the analysis. Soil properties for each of the soil layers encountered were conservatively estimated based upon published literature and past experience with soils of these types. Longterm strength parameters for the in-situ glacial till and glacial till utilized as fill for embankment construction were estimated based upon Properties and Behaviour of Till as Construction Material prepared by Andre A. Loiselle and Jacques E. Hurtubise, and Geotechnical Aspects of Glacial Tills, prepared by V. Milligan, both presented in the publication entitled Glacial Till, published by The Royal Society of Canada in Copies of these papers have been included in Appendix G. As the glacial till is generally of a granular nature, it has been assumed that the drained and undrained 1.0 7

11 C. T. MALE ASSOCIATES, P.C. parameters are equal. Due to the plasticity observed within recovered samples from the overlying silt deposit, this deposit was estimated to behave as a cohesive soil. Undrained and drained strength parameters for the silt were estimated based upon both laboratory and field testing of similar soils. The peak ground acceleration utilized in Load Case VII was obtained from the USGS Interactive Hazard Deaggregation website for a seismic event with a 2-percent chance of exceedence in 50 years, or a return period of 2,475 years. A copy of the Interactive Hazard Deaggregation Graph is included in Appendix H. This return period corresponds to the 10-percent chance of exceedence in 250 years noted in the letter (Section 3.3(h)(i)) dated August 20, 2010 regarding SEQR Review for the project. As also noted in the referenced section, a seismic impact zone refers to an area with a 10 percent or greater probability that the maximum horizontal acceleration in lithified earth material, expressed as a percentage of the earth s gravitational pull (g), will exceed 0.10g in 250 years as delineated on the most current version of the United States Geological Survey Map. For the Brine Pond site, this peak ground acceleration is equal to 0.071g, which does not exceed 0.10g. Irrespective of this, a seismic analysis was still conducted for the proposed brine pond utilizing a peak ground acceleration of 0.071g. 6.0 ANALYSIS & RECOMMENDATIONS 6.1 Drainage Course Analysis As evident from the Subsurface Profiles and Groundwater Contour Map presented in Appendix A, establishment of bottom-of-pond elevations will require lowering of the site grades up to 15 feet below the existing groundwater table elevation as measured at groundwater monitoring well locations. To estimate the quantity of water expected to be encountered during construction of the brine pond, Darcy s Law was utilized in conjunction with the observations noted during the subsurface investigation program. For calculation purposes, the hydraulic conductivity was assumed to be equal to 1.3 x 10-2 centimeters per second (cm/s), which as previously noted, was recorded during slug testing of a groundwater monitoring well screened within the weathered/broken bedrock. The hydraulic gradient was estimated based upon groundwater readings taken at monitoring well location MW-5 and the contours shown on the Groundwater Contour Map, Drawing SI-4. From the Subsurface Profiles included in Appendix A, it is estimated that a maximum of 6.5 feet of bedrock excavation will be required along approximately 600 lineal feet of the western (uphill) embankment to establish proposed elevations. For calculation purposes, it was assumed that this results in an approximate area of groundwater seepage through the weathered bedrock of nearly 2,000 square feet. Utilizing the permeability value indicated above, the quantity of water to be expected in the excavation through the weathered bedrock would be between 50 and 100 gallons per minute (gpm). 8

12 C. T. MALE ASSOCIATES, P.C. The capacity of the crushed stone drainage course to convey the expected flow from the cut slope was approximated in a similar fashion to that described above. The hydraulic gradient utilized in the calculation was modified, as the crushed stone extends no further than elevation 825 feet, which results in a hydraulic gradient of 0.2. Using these parameters, it was estimated that the crushed stone drainage course could handle approximately 140 cubic centimeters per second, or 100,000 times the expected quantity of flow emanating from the cut slope. 6.2 Slope Stability Analysis The stability analysis was conducted for each of three (3) sections: one (1) each along the northern and southern ends of the pond in an east-west direction; and one (1) in a north-south direction through the northern and southern embankments. In this analysis, it was assumed that the underdrain to be installed along the western (uphill) side of the embankment together with the drainage blanket to be installed across the base of the pond will locally depress the groundwater table at the toe of this slope. Above the slope s toe, the 14-inch thick drainage layer of crushed stone installed on the slope will intercept any groundwater flow. Accordingly, with the thickness and gradation of the drainage course sized to transmit this flow, the analysis modeled the groundwater profile above the toe as being inclined and, up to a level just above the seasonally high groundwater table, running along the base of the drainage course. Above this level, the groundwater table was assumed to be uninfluenced by the drainage course and/or toe drain until reaching the interceptor drain located below the drainage swale along the uphill (western) embankment. Groundwater elevations were assumed to be locally depressed at this location prior to returning to the level shown on the Groundwater Contour Plan. Using the strength parameters as discussed in Section 5 above and the design elements presented in this Section, the range of minimum calculated factors of safety for the various sections under each Loading Condition is shown in Table 2 below. Computer output generated by GEOSLOPE for each of the analyzed sections and Load Cases is included in Appendix I. Summary tables presenting the calculated factor of safety for each of the load cases analyzed at each section preface the computer generated output presented in Appendix I. 9

13 C. T. MALE ASSOCIATES, P.C. Case No. I II Loading Condition End-of-Construction Long-Term with Steady Seepage and Maximum Storage Pool (including Design Rainfall Event) Table 2 Computed Factors of Safety Slope Analyzed Inside & Outside Range of Calculated Factors of Safety Min. Required Factor of Safety 2.25 to Outside 2.25 to IV Rapid Drawdown Inside 1.84 to VII Earthquake Case II with Seismic Loading Inside & Outside 1.74 to Based upon our analysis, the computed factors of safety for the embankments under each of the Loading Conditions described above are in excess of the minimum required factor of safety. The magnitude of the peak ground acceleration was doubled over that provided by the USGS (0.071g to 0.142g), and an additional analysis was conducted to determine the stability of the section with the lowest factor of safety under Load Case VII. Even under this greatly increased peak ground acceleration, the calculated factor of safety under Load Case VII was determined to be in excess of Design Recommendations As indicated in Section 6.1, a 6-inch perforated PVC underdrain will be installed beneath the drainage swale along the western (uphill) embankment. The invert of the pipe will be installed a maximum of 8 feet beneath the bottom of the drainage swale along the western embankment and be located beneath the drainage swale s eastern slope. The underdrain will be bedded in crushed stone, wrapped in geotextile, and allowed to daylight into the drainage swale that wraps around the exterior of the northern and southern embankments. In order to capture and discharge groundwater to relieve hydrostatic pressures that may induce heave of the subgrade soils, cutoff trenches will be constructed parallel to the toe of the western embankment at or near elevation 812 feet. The trenches will contain perforated 10-inch diameter PVC pipes bedded in crushed stone and wrapped in geotextile. In addition to the cutoff trenches, perforated underdrains varying in size from 6 to 12 inches in diameter will be placed within the course of No. 1 and No. 1A crushed stone underlying the pond s liner system. The underdrains will have a 10

14 C. T. MALE ASSOCIATES, P.C. minimum pitch of 0.5 percent to provide the requisite flow capacity. These underdrains will convey the groundwater downstream and discharge into existing swales. The course of crushed stone will have a minimum thickness of 14 inches along the base of the pond and extend up the northern, southern and western embankments to a minimum elevation of feet. Along the eastern (downstream) embankment, the crushed stone will extend up the slope a minimum of 10 feet beyond the toe of the embankment. 6.4 Construction Recommendations The presence of fine grained soils in large quantities within the overburden means that the fill soils will be relatively poorly drained, which will result in the buildup of excess pore water pressures within the soil as the embankments are constructed. In addition, as indicated in the previously referenced Geotechnical Aspects of Glacial Till, where glacial till is utilized as a construction material, close control over the material s water content is essential as the material tends to become unstable when wet of the material s optimum moisture content as defined by the Proctor Compaction Test. Accordingly, it is crucial that all fill placed at the site be placed dry of optimum, with a water content less than the material s optimum moisture content. As noted in Control of Construction Pore Pressures of Earth and Earth-Rock Dams (included in Appendix G), by placing the material dry of optimum, excess pore water pressures within the fill will also be reduced. In keeping with the comments above, construction of the impoundment s embankment must be performed in a controlled manner. The overburden present at the site is laden with cobbles and boulders, and contains water bearing granular seams. Particles greater than 12 inches in size must be culled from the excavated soils as they are placed as fill. In addition, as the excavated material may be wet upon its excavation, it may require disking to aerate and dry it to a moisture content at which it can be compacted to the degree required. The fill should be placed in maximum loose lift thicknesses of 12 inches and be compacted to a dry density equal to at least 95 percent of the material s maximum dry density as it is defined by the Standard Proctor Compaction Test, ASTM D-698. The moisture content at which this degree of compaction is achieved should be at or within 3 percent below the optimum moisture content defined by this standard. The subgrade soils composed of glacial till, whether natural or placed as fill to construct the impoundment embankment, will be sensitive to disturbance. The natural soils are expected to be wet and will tend to rut and/or pump and weave under repeated traffic of earthmoving equipment. Final preparation of the subgrade surface across the impoundment s bottom will include back-blading of the surface to infill any ruts and light proofrolling of its surface to provide a relatively smooth and stable surface for 11

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16 APPENDIX A Subsurface Investigation Plan & Profiles

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21 APPENDIX B Subsurface Exploration Logs

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43 APPENDIX C Test Pit Logs

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57 APPENDIX D Groundwater Monitoring Well Construction Logs

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