For. Final Report of Geotechnical Exploration. JEA Main Street WTP Well No. 15 Jacksonville, Florida

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1 Final Report of Geotechnical Exploration For JEA Main Street WTP Well No. 1 Jacksonville, Florida MAE Project No A April 7, 017 Prepared for: Prepared by: 896 Western Way, Suite 1 Jacksonville, Florida 6 Phone (904) Fax (904)

2 April 7, 017 CDM Smith, Inc. 881 Dix Ellis Trail, Suite 400 Jacksonville, Florida 6 Attention: Reference: Mr. Yanni Polematidis, P.E. Final Report of Geotechnical Exploration JEA Main Street WTP Well No. 1 Jacksonville, Florida MAE Project No A P. Rodney Mank, State of Florida, Professional Engineer, License No This item has been electronically signed and sealed by P. Rodney Mank, P.E. on 04/07/017 using a Digital Signature. Printed copies of this document are not considered signed and sealed and the signature must be verified on any electronic copies. Dear Mr. Polematidis: Meskel & Associates Engineering, LLC (MAE) has completed a geotechnical exploration for the subject project. Our work was performed in general accordance with our proposal dated October 17, 016, and was authorized by your subcontractor agreement dated March 1, 017. The purpose of our exploration was to evaluate the subsurface conditions encountered along the proposed pipeline route and at the proposed pump pad to provide pump pad foundation design recommendations and recommendations for pipe bedding, backfilling, and site preparation. In summary, we understand that this project consists of constructing a concrete slab-on-grade pad to support the pump equipment associated with the proposed JEA water supply well, and installing a 16 Ductile Iron raw water pipeline from Well 1 to the abandoned Well 8 located across East nd Street. The subsurface soils encountered at the pad location and along the proposed pipeline alignment generally consisted of fine sands and fine sands with silt (SP, SP-SM/A-) to depths of 4 to 6 feet, underlain by silty fine sands (SM/A--4) to the termination depth of 10 feet at the pipeline borings, and to a depth of about 1. feet at the pad location. The silty sands were underlain by fine sands with silt (SP-SM) to the terminating depth of 0 feet below existing grade at the pad location. Based on our findings, it is our opinion that the encountered subgrade soils are adaptable to support the pump pad. The encountered soils are also suitable as pipe bedding for the raw water main and as pipe backfill. We appreciate this opportunity to be of service as your geotechnical consultant on this phase of the project. If you have any questions, or if we may be of further service at this time, please contact us. Sincerely, MESKEL & ASSOCIATES ENGINEERING, LLC MAE FL Certificate of Authorization No. 814 W. Josh Mele, E.I. Staff Engineer Distribution: signed by Philip R Digitally Philip R Mank Date: Mank 14:06:1-04'00' P. Rodney Mank, P.E. Principal Engineer Registered, Florida No Mr. Yanni Polematidis, P.E. CDM Smith, Inc. 896 Western Way, Suite 1 Jacksonville, Florida 6 Phone: (904) Fax: (904) pdf

3 JEA Main Street WTP Well No. 1 MAE Final Report No A TABLE OF CONTENTS Subject Page No. PROJECT INFORMATION... 1 Project Description... 1 Site Conditions... 1 FIELD EXPLORATION... 1 LABORATORY TESTING... Soil Index Tests... Corrosion Series Tests... SITE GENERAL SUBSURFACE CONDITIONS... General Soil Profile... Groundwater Level... Seasonal High Groundwater Level... Soil Corrosion Potential... DESIGN RECOMMENDATIONS... 4 General... 4 Well Pad Foundation Design Recommendations... 4 Pipeline Support Recommendations... Seismic Site Classification... 6 SITE PREPARATION AND EARTHWORK RECOMMENDATIONS... 6 Clearing and Stripping... 6 Temporary Groundwater Control... 6 Compaction of Pad Subgrade Soils... 7 Foundation Areas... 7 Preparation of Pipe Bedding Soils... 7 Compaction of Pipeline Excavation Bottom... 7 Excavation Protection... 8 Structural Backfill and Compaction of Structural Backfill... 8 QUALITY CONTROL TESTING... 9 REPORT LIMITATIONS... 9 FIGURES Figure 1. Figure. Figure. APPENDICES Appendix A. Appendix B. Site Location Plan Boring Location Plan Generalized Soil Profiles Soil Boring Logs Key to Boring Logs Field Exploration Procedures Key to Soil Classification Summary of Laboratory Test Results Summary of Corrosion Series Test Results Laboratory Test Procedures 896 Western Way, Suite 1 Jacksonville, Florida 6 Phone: (904) Fax: (904) Page i

4 JEA Main Street WTP Well No. 1 MAE Final Report No A 1.0 PROJECT INFORMATION 1.1 Project Description The site for the Well 1 pump pad is located at the northwest corner of the intersection of East nd Street and Clark Street in Jacksonville, Duval County, Florida. The general site location is shown on Figure 1. In summary, we understand that this project will consist of installing a new production well for JEA at the project site. A cast-in-place concrete, monolithic turned-down-edge slab will be designed to support the pump equipment. We understand the slab dimensions will be approximately 1 feet by 7 feet. We have assumed a uniform slab load of 600 psf accounting for the planned pump equipment and slab weight. In addition, a 16-inch diameter Ductile Iron raw water pipeline will be constructed to service the production well. It will be constructed to have a minimum cover of approximately feet along the proposed pipeline alignment using the open cut method. We recommend that MAE be allowed to review the final project plans and specifications prior to construction to verify that the recommendations provided in this report have been properly interpreted and followed. If final project design details vary from those provided for this report, then the recommendations in this report may need to be re-evaluated. Any changes in these conditions should be provided so the need for re-evaluation of our recommendations can be assessed prior to final design. 1. Site Conditions The area of the proposed pump pad and pipeline route at the time of our field exploration was developed with surface cover consisting of asphalt surfaced pavement and grass in non-paved areas. The area was relatively flat across the planned construction area. Surface drainage appeared to be into the existing soils in non-paved areas, and directed to the stormwater collection system in the paved areas..0 FIELD EXPLORATION Our field exploration was performed at the site on March 9, 017. The soil boring locations were determined by CDM and shown on a sheet titled Proposed Site Layout JEA Well No. 1 dated February 017. The borings were located in the field by a MAE technician using the State Plane coordinates as shown on the sheet and converting them to GPS coordinates. The locations were adjusted based on known underground utilities as identified by JEA personnel. The final, staked boring locations are shown on the attached Boring Location Plan, Figure, which is a partial copy of the plan sheet provided to us. The locations shown on Figure should be considered approximate based on the method of layout used. Three Standard Penetration Test (SPT) borings were located within the proposed construction area to explore the subsurface conditions. One SPT boring (B-1) was located within the planned pump pad area and was drilled to a depth of 0 feet below the existing ground surface. The other two borings (B- and B-) were located along the planned pipeline route. Each boring was drilled to a depth of 10 feet below existing ground surface. 896 Western Way, Suite 1 Jacksonville, Florida 6 Phone: (904) Fax: (904) Page 1

5 JEA Main Street WTP Well No. 1 MAE Final Report No A The SPT borings were performed in general accordance with the methodology outlined in ASTM D 186. Boring B- was located within existing pavement and was first advanced by hand to a depth of 6 feet using a hand-held bucket auger due to possible utility conflicts. A Static Cone Penetrometer was used to estimate the relative density of the encountered soils. The split-spoon and bucket auger soil samples recovered during performance of the borings were visually described in the field by the field crew. Representative soil samples recovered from the borings were returned to the laboratory for classification by a geotechnical engineer and assignment of laboratory tests. Once the borings were complete, they were backfilled with soil cuttings. Boring B- was capped with an asphalt coldpatch material..0 LABORATORY TESTING Representative soil samples obtained during our field exploration were visually classified by a geotechnical engineer using the AASHTO Classification System in general accordance with ASTM D 8 (pipeline borings B- and B-), and the Unified Soil Classification System (USCS) in general accordance with ASTM D 487 (pump pad boring B-1). A key for both soil classification systems is included in Appendix B..1 Soil Index Tests Quantitative laboratory testing was performed on selected samples of the soils encountered during the field exploration to better define their composition and to provide data for correlation to their anticipated strength and compressibility characteristics. The laboratory testing determined the percent fines and the natural moisture contents of the selected soil samples. The results of the laboratory testing are shown on the Summary of Laboratory Test Results table included in Appendix B. These results are also shown on the Generalized Soil Profiles, Figure, and on the boring logs (Appendix A) at the approximate depth from which the tested samples were recovered.. Corrosion Series Tests Two soil samples were selected from borings B- and B- along the proposed pipeline route for corrosion potential testing. The testing included soil ph, resistivity, and chloride and sulfate contents. The soil corrosion potential is discussed in Section 4.4 below. A summary table of the laboratory test results and the environmental classifications is presented in Appendix B. 4.0 SITE GENERAL SUBSURFACE CONDITIONS 4.1 General Soil Profile Presentation of the generalized subsurface conditions is presented on the Generalized Soil Profiles, Figure. Detailed boring logs are included in Appendix A. When reviewing the Profiles and the logs, it should be expected that soil conditions will vary away from the boring locations. In general, the boring within the planned pump pad area (B-1) encountered a surficial topsoil layer, approximately inches in thickness. Below the topsoil layer, the boring encountered possible fill soil consisting of loose fine sand with silt (SP-SM) and gravel (rock fragments) to a depth of about feet below the existing ground surface. Below the apparent fill soil, the boring encountered medium dense fine sands (SP) to a depth of about 4 feet, underlain by medium dense silty fine sands (SM) to a depth of about 1. feet below the existing ground surface. Below the silty sand soil, the boring 896 Western Way, Suite 1 Jacksonville, Florida 6 Phone: (904) Fax: (904) Page

6 JEA Main Street WTP Well No. 1 MAE Final Report No A encountered dense fine sands with silt (SP-SM) to the terminating depth of 0 feet below the existing ground surface. The borings along the proposed pipeline route (B- and B-) encountered a 4-inch thick topsoil layer and a flexible pavement section consisting of ¾-inches of asphalt surface course underlain by 6 inches of limerock base, respectively. Below these surficial layers, the borings encountered loose to medium dense fine sands with silt (A-) to a depth of 6 feet below the existing ground surface. Underlying the sand soils were loose silty fine sands to a depth of about 8 feet, underlain by medium dense fine sands with silt (A-) to the terminating depth of 10 feet. 4. Groundwater Level The groundwater level was encountered at each of the borings. The measured groundwater levels varied from feet, 11 inches to 6 feet below the existing ground surface. The depths to the groundwater level are shown on the Generalized Soil Profiles sheet (Figure ) and on the boring logs. It should be anticipated that fluctuations in groundwater levels will occur due to seasonal variations in the amount of rainfall, altered surface water runoff patterns, construction operations, and other factors. 4. Seasonal High Groundwater Level In estimating the seasonal high groundwater level, a number of factors are taken into consideration including antecedent rainfall, soil redoximorphic features (i.e., soil mottling), stratigraphy (including presence of hydraulically restrictive layers), vegetative indicators, effects of development, and relief points such as drainage ditches, low-lying areas, etc. It is apparent, based on the observed site conditions and the subsurface soil profile encountered in the borings, that the project site has been previously graded and filled for the construction of the existing site improvements. Therefore, the pre-development subsurface conditions that would have provided evidence of historical seasonal groundwater fluctuations have been altered. Furthermore, development in the area has likely altered drainage patterns and, thus, the seasonal water level fluctuations in the project area. Based on the encountered subsurface conditions as shown on the boring logs, we estimate the current Seasonal High Groundwater Level at the site to be about 1 to feet above the measured groundwater levels. It is possible that groundwater levels may temporarily exceed the estimated seasonal high groundwater level because of significant or prolonged rains. Therefore, we recommend that the contractor measure the depth to the groundwater level at the time of construction to determine how this will affect construction and whether dewatering as further discussed in Section 6. below will be necessary. 4.4 Soil Corrosion Potential As discussed in Section. above, two soil samples were selected for testing of corrosion potential. The tests included soil ph, resistivity, and soil sulfate and chloride contents. The test results are summarized on a table located in Appendix B. Table Criteria for Substructure Environmental Classifications from the FDOT s Structures Design Guidelines (January 016 edition) was used to determine the soil corrosion potential for steel and concrete substructures. In summary, the soils are classified as Slightly to Extremely Aggressive for steel substructures due to the sample ph levels. For concrete substructures, the soils are classified as Slightly to Moderately Aggressive due to the sample ph levels. 896 Western Way, Suite 1 Jacksonville, Florida 6 Phone: (904) Fax: (904) Page

7 JEA Main Street WTP Well No. 1 MAE Final Report No A.0 DESIGN RECOMMENDATIONS.1 General The following geotechnical engineering evaluation and recommendations are based on the results of the field and laboratory testing performed, our experience with similar soil conditions, and an understanding of the provided project information as presented in this report. If the project information presented in this report is incorrect, please contact us so these recommendations can be reviewed. Also, the discovery of any site or subsurface conditions during construction which deviate from the data presented herein should be reported to us for evaluation. We recommend that we be provided the opportunity to review the plans and earthwork specifications to verify that our recommendations have been properly interpreted and implemented.. Well Pad Foundation Design Recommendations Based on the results of our exploration, we consider the subsurface conditions at the pump pad site adaptable for support of the proposed structure when constructed on a properly designed monolithic slab foundation system. Provided the site preparation and earthwork construction recommendations outlined in Section 6.0 of this report are performed, the following parameters may be used for foundation design...1 Bearing Pressure The maximum allowable net soil bearing pressure for use in shallow foundation design should not exceed,000 psf. Net bearing pressure is defined as the soil bearing pressure at the foundation bearing level in excess of the natural overburden pressure at that level. The foundations should be designed based on the maximum load that could be imposed by all loading conditions... Foundation Size The minimum widths recommended for the turned-down-edge portion of the monolithic slab should 16 inches. Even though the maximum allowable soil bearing pressure may not be achieved, these width recommendations should control the size of the foundations... Bearing Depth The turned-down-edge portion of the slab should bear at a depth of at least 1 inches below the exterior final grades to provide confinement to the bearing level soils. It is recommended that stormwater be diverted away from the slab to reduce the possibility of erosion beneath the slab...4 Bearing Material The turned-down-edge may bear in either the compacted suitable natural soils or compacted structural fill. The bearing level soils, after compaction, should exhibit densities equivalent to 98 percent of the modified Proctor maximum dry density (ASTM D 17), to a depth of at least one foot below the foundation bearing levels... Settlement Estimates Post-construction settlement of the slab will be influenced by several interrelated factors, such as (1) subsurface stratification and strength/compressibility characteristics; () the size and bearing level 896 Western Way, Suite 1 Jacksonville, Florida 6 Phone: (904) Fax: (904) Page 4

8 JEA Main Street WTP Well No. 1 MAE Final Report No A of the turned-down-edge portion of the slab, the applied loads and resulting bearing pressures beneath the slab; and () site preparation and earthwork construction techniques used by the contractor. Our settlement estimates for the slab are based on the use of site preparation/earthwork construction techniques as recommended in Section 6.0 of this report. Any deviation from these recommendations could result in increased post-construction settlements of the slab. Due to the sandy nature of the near-surface soils, we expect the majority of settlement to occur in an elastic manner and fairly rapidly during construction. Using the recommended maximum bearing pressure and the field and laboratory test data that we have correlated to geotechnical strength and compressibility characteristics of the subsurface soils, we estimate that total settlement of the structure could be on the order of one inch or less. Differential settlements result from differences in applied bearing pressures and variations in the compressibility characteristics of the subsurface soils. Because of the general uniformity of the subsurface conditions and the recommended site preparation and earthwork construction techniques outlined in Section 6.0, we anticipate that differential settlements of the slab should be on-half inch or less...6 Slab The pump pad can be constructed as a slab-on-ground, provided unsuitable material is removed and replaced with compacted structural fill as outlined in Section 6.0. We recommend that a slab subgrade modulus of 10 pci be used for slab design, assuming the site preparation recommendations provided in Section 6.0 below are followed. In addition, we recommend that a minimum separation of feet be maintained between the finished floor levels and the estimated seasonal high groundwater level.. Pipeline Support Recommendations Based on the results of the subsurface explorations, laboratory testing, and provided information, as included in this report, we consider the subsurface conditions at the site adaptable for supporting the proposed raw water pipeline when constructed upon properly prepared subgrade soils as noted in Section 6 of this report. As noted in Section 4.1 above, boring B- encountered a topsoil layer about 4 inches in thickness. Boring B- encountered a flexible pavement section consisting of ¾ inches of asphalt surface course underlain by 6 inches of limerock base. Below these surficial layers, the borings encountered loose to medium dense fine sands with silt (A-) 6 feet below the existing ground surface. Underlying the sand soils were loose silty fine sands to a depth of about 8 feet, underlain by medium dense fine sands with silt (A-) to the terminating depth of 10 feet below existing the existing ground surface. We understand that the pipe invert elevation will be approximately 4 to feet below the existing ground surface. Therefore, it is likely that the pipe excavation will encounter loose to medium dense fine sands with silt (A-) at the pipe invert elevation. These soils are suitable for use as pipe bedding and should be able to be compacted provided the moisture content can be controlled through proper dewatering...1 Hydrostatic Uplift Resistance It is anticipated that the buried pipe will exert little or no net downward pressure on the soils, rather, the structures may be subject to hydrostatic uplift pressure when empty. Underground structures should be designed to resist hydrostatic uplift pressures appropriate for their depth below existing 896 Western Way, Suite 1 Jacksonville, Florida 6 Phone: (904) Fax: (904) Page

9 JEA Main Street WTP Well No. 1 MAE Final Report No A grade and the normal seasonal high groundwater table. Hydrostatic uplift forces can be resisted in several ways including: Addition of dead weight to the structure. Mobilizing the dead weight of the soil surrounding the structure through extension of footings outside the perimeter of the structure. A soil unit weight of 10 lb/ft and a soil friction angle of 0 degrees may be used in designing structures to resist buoyancy..4 Seismic Site Classification We reviewed the site class definitions from the 016 International Building Code (Section 161..) to determine the general Site Class for the site. Because of the limited depth of the soil borings, the Code allows Site Class D to be used as no data obtained from this exploration would result in a Site Class of E or F. 6.0 SITE PREPARATION AND EARTHWORK RECOMMENDATIONS Site preparation as outlined in this section should be performed to provide more uniform foundation bearing conditions and to reduce the potential for post-construction settlements of the planned pump pad and raw water pipeline. 6.1 Clearing and Stripping Prior to construction, the location of existing underground utility lines within the construction area should be established. Provisions should then be made to relocate interfering utilities to appropriate locations. It should be noted that if underground pipes are not properly removed or plugged, they may serve as conduits for subsurface erosion which may subsequently lead to excessive settlement of overlying structures. The "footprint" of the proposed pump slab plus a minimum additional margin of feet should be stripped of all surface vegetation, stumps, debris, organic topsoil, or other deleterious materials. Based on the results of the soil boring at the well pad location, it should be anticipated that up to 6 inches of surficial organics will be encountered at the surface that will need to be stripped from the construction area. During grubbing operations, roots with a diameter greater than 0.-inch, stumps, or small roots in a concentrated state, should be grubbed and completely removed. The pipeline construction area will encounter pavement layers (asphalt surface plus base layer) with a total thickness of about 6-/4 inches based on boring B-, and a topsoil thickness of about 4 inches based on boring B-. These pavement and organic materials should be stripped and removed from the construction area prior to pipe excavation. The actual depths of removal should be determined by MAE using visual observation and judgment during earthwork operations. Any topsoils removed from the construction area can be stockpiled and used subsequently in areas to be grassed. 6. Temporary Groundwater Control The groundwater level was encountered at the boring locations at a depth of about 6 feet below the existing ground surface at the time of our exploration. Because of the need for excavation to the raw water pipeline bearing levels, it may be necessary to install temporary groundwater control measures to dewater the area to facilitate the excavation and compaction processes. The 896 Western Way, Suite 1 Jacksonville, Florida 6 Phone: (904) Fax: (904) Page 6

10 JEA Main Street WTP Well No. 1 MAE Final Report No A groundwater control measures should be determined by the contractor but can consist of sumps or wellpoints (or a combination of these or other methods) capable of lowering the groundwater level to at least feet below the required depth of excavation. The dewatering system should not be decommissioned until excavation, compaction, and fill placement is complete. The contractor should verify the depth to ground water before construction processes begin. 6. Compaction of Pad Subgrade Soils After completing the clearing and stripping operations at the pump pad location and installing the temporary groundwater control measures (if required), the exposed surface area should be compacted with a vibratory drum roller having a minimum static, at-drum weight, on the order of 10 tons. Typically, the material should exhibit moisture contents within ± percent of the modified Proctor optimum moisture content (ASTM D 17) during the compaction operations. Compaction should continue until densities of at least 98 percent of the modified Proctor maximum dry density (ASTM D 17) have been achieved within the upper feet of the compacted natural soils at the site. Should the bearing level soils experience pumping and soil strength loss during the compaction operations, compaction work should be immediately terminated. The disturbed soils should be removed and backfilled with dry structural fill soils, which are then compacted, or the excess moisture content within the disturbed soils should be allowed to dissipate before recompacting. Care should be exercised to avoid damaging any nearby structures while the compaction operation is underway. Prior to commencing compaction, occupants of adjacent structures should be notified, and the existing conditions of the structures should be documented with photographs and survey (if deemed necessary). Compaction should cease if deemed detrimental to adjacent structures, and Meskel & Associates Engineering should be contacted immediately. It is recommended that the vibratory roller remain a minimum of 0 feet from existing structures. Within this zone, use of a track-mounted bulldozer or a vibratory roller, operating in the static mode, is recommended. 6.4 Foundation Areas After satisfactory compaction of the pad subgrade soils, and placement and compaction of any required structural fill, the foundation areas may be excavated to the planned bearing levels. The foundation bearing level soils, after compaction, should exhibit densities equivalent to 98 percent of the modified Proctor maximum dry density (ASTM D 17), to a depth of one foot below the bearing level. For confined areas, such as the footing excavations, any additional compaction operations can probably best be performed by the use of a lightweight vibratory sled or roller having a total weight on the order of 00 to 000 pounds. 6. Preparation of Pipe Bedding Soils The proposed pipeline is anticipated to bear in sandy (A-) soils. Therefore, the soils should be excavated to the proposed bearing elevation and the exposed excavation surface should be compacted as outlined in Section 6. below. Once the bedding soils are satisfactorily compacted, backfilling can commence with suitable compacted structural fill as discussed in Section 6.7 below. Once the pipe is installed, the trench should be backfilled with compacted structural backfill to final grade as discussed in Section Compaction of Pipeline Excavation Bottom After installing the temporary groundwater control measures and achieving the required depth of excavation for the pipeline, the exposed surface of sandy soils should be compacted by the use of 896 Western Way, Suite 1 Jacksonville, Florida 6 Phone: (904) Fax: (904) Page 7

11 JEA Main Street WTP Well No. 1 MAE Final Report No A hand-operated equipment. Typically, the material should exhibit moisture contents within ± percent of the modified Proctor optimum moisture content (AASHTO T-180) during the compaction operations. Compaction should continue until densities of at least 98 percent of the modified Proctor maximum dry density (AASHTO T-180) have been achieved within the upper one foot below the exposed surface within the pipeline excavation. Should the bearing level soils experience pumping and soil strength loss during the compaction operations, compaction work should be immediately terminated and (1) the disturbed soils removed and backfilled with dry structural fill soils which are then compacted, or () the excess moisture content within the disturbed soils allowed to dissipate before recompacting. Care should be exercised to avoid damaging any nearby structures while the compaction operations are underway. Compaction should cease if deemed detrimental to adjacent structures. 6.7 Excavation Protection Excavation work for the force main construction will be required to meet OSHA Excavation Standard Subpart P regulations for Type C Soils. The use of excavation support systems will be necessary where there is not sufficient space to allow the side slopes of the excavation to be laidback to at least H:1V ( horizontal to 1 vertical) to provide a safe and stable working area and to facilitate adequate compaction along the sides of the excavation. In addition, it should be anticipated that an excavation support system may be necessary to protect adjacent existing structures, pavement and/or utilities that are located along the proposed pipeline alignment. The method of excavation support should be determined by the contractor but can consist of a trench box, drilled-in soldier piles with lagging, interlocking steel sheeting or other methods. The support structure should be designed according to OSHA sheeting and bracing requirements by a Florida registered Professional Engineer. Where pipeline excavations and the construction of excavation support systems are within 0 feet of existing structures and the adjacent roadway, the existing structures and roadway should be monitored for adverse reactions to construction vibrations and dewatering activities. 6.8 Structural Backfill and Compaction of Structural Backfill Any structural backfill or fill required for the pump pad should be placed in loose lifts not exceeding 1 inches in thickness and compacted by the use of the above described vibratory drum roller. The lift thickness should be reduced to 8 inches if the roller operates in the static mode or if trackmounted compaction equipment is used. If hand-held compaction equipment is used, the lift thickness should be further reduced to 6 inches. Structural backfill placed for the proposed pipeline should be placed in loose lifts not exceeding six inches in thickness and compacted using hand-operated compaction equipment. This procedure should continue until the backfill level is 4 inches above the top of the pipeline. At ground surface elevations greater than 4 inches above the top of the pipeline, structural backfill may be placed in loose lifts not exceeding 1 inches in thickness. Care should be taken to not damage the underlying pipeline during compaction. Structural backfill is defined as a non-plastic, granular soil having less than 10 percent material passing the No. 00 mesh sieve and containing less than 4 percent organic material. The sandy soils (A-) excavated for the pipeline may be used as backfill. Typically, the backfill material should exhibit moisture contents within ± percent of the modified Proctor optimum moisture content (AASHTO T180) during the compaction operations. Compaction should continue until densities of at least Western Way, Suite 1 Jacksonville, Florida 6 Phone: (904) Fax: (904) Page 8

12 JEA Main Street WTP Well No. 1 MAE Final Report No A percent of the modified Proctor maximum dry density (AASHTO T-180) have been achieved within each 6- or 1-inch-thick lift of the compacted structural backfill below the pump pad or under pavements, or 9 percent of maximum dry density outside of pavement areas. The silty sands (A--4) encountered in the pipeline borings may be suitable for use as backfill. However, it should be noted that soils with more than 10 percent passing the No. 00 sieve will be more difficult to compact, due to their nature to retain soil moisture, and may require long drying periods to render them suitable for use as backfill. We recommend that material excavated from the pipeline trenches which will be reused as backfill be stockpiled a safe distance from the excavations and in such a manner that promotes runoff away from the open trenches and limits saturation of the materials. 7.0 QUALITY CONTROL TESTING A representative number of field in-place density tests should be made in the upper feet of the soils, and in each lift of compacted backfill and fill. The density tests are considered necessary to verify that satisfactory compaction operations have been performed. We recommend density testing be performed at a minimum of one location for every 10 feet of pipeline, and at a minimum of two locations within the footprint of the pump pad. 8.0 REPORT LIMITATIONS This report has been prepared for the exclusive use of JEA and their consultants for specific application to the design and construction of the JEA Main Street WTP Well No. 1 project. Our work for this project was performed in accordance with generally accepted geotechnical engineering practice. No warranty, express or implied, is made. The analyses and recommendations contained in this report are based on the data obtained from the borings performed for the JEA Main Street WTP Well No. 1 project. This testing indicates subsurface conditions only at the specific locations and times, and only to the depths explored. These results do not reflect subsurface variations that may exist away from the boring locations and/or at depths below the boring termination depths. Subsurface conditions and water levels at other locations may differ from conditions occurring at the tested locations. In addition, it should be understood that the passage of time may result in a change in the conditions at the tested locations. If variations in subsurface conditions from those described in this report are observed during construction, the recommendations in this report must be re-evaluated. If changes in the design or location of the pipeline or pump pad occur, the conclusions and recommendations contained in this report may need to be modified. We recommend that these changes be provided to us for our consideration. MAE is not responsible for conclusions, interpretations, opinions or recommendations made by others based on the data contained in this report. 896 Western Way, Suite 1 Jacksonville, Florida 6 Phone: (904) Fax: (904) Page 9

13 Figures

14 N Approximate Site Location Site Location Map PREPARED BY PROJECT NAME JEA Main Street Water Treatment Plant Well Number 1 Jacksonville, Florida REFERERENCE SCALE Delorme XMap 7.0 NTS PREPARED FOR MAE PROJECT NO. FIGURE NO. CDM Smith, Inc A 1

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16 0 4 B-1 Latitude: 'N Longitude: 'W N N N Topsoil (") Topsoil (4") 10 Loose, Very dark gray fine SAND with silt, few gravel (rock fragments), poorly graded. (SP-SM) Medium dense, Very pale brown fine SAND, poorly graded. (SP) B- Latitude: 0 0.'N Longitude: 'W 8 Loose, Brown fine SAND with silt, poorly graded. (A-) Medium dense, Very pale brown fine SAND with silt, poorly graded. (A-) B- Latitude: 'N Longitude: 'W *HA Asphalt (/4") Limerock Base (6") Medium dense, Light yellowish brown fine SAND with silt, poorly graded. (A-) Medium dense, Light brownish gray fine SAND with silt, poorly graded. (A-) Loose, Light gray fine SAND with silt, poorly graded. (A-) Medium dense, Light gray fine SAND with silt, poorly graded. (A-) 6 Loose, Light gray silty fine SAND, poorly graded. (A--4) w = 6-00 = 11 Loose, Light gray silty fine SAND, poorly graded. (A--4) 6 8 Medium dense to loose, Light gray silty fine SAND, poorly graded. (SM) w = 4-00 = 9 8 Medium dense, Light gray fine SAND with silt, poorly graded. (A-) 8 Medium dense, Light gray fine SAND with silt, poorly graded. (A-) '. Date Drilled: /9/017 Boring backfilled with soil cuttings. 10'. Date Drilled: /9/017 Boring backfilled with soil cuttings and capped with Asphalt Cold Patch Depth (ft) Depth (ft) 16 Dense, Very pale brown fine SAND with silt, poorly graded. (SP-SM) '. Date Drilled: /9/017 Boring backfilled with soil cuttings. 0 Topsoil Fine Sand with Silt Fine Sand Silty Fine Sand Asphalt Limerock Base N BT Legend Standard Penetration Resistance, Blows/Foot Boring Terminated at Depth Below Existing Grade (A-) AASHTO Soil Classification System (SP) Unified Soil Classification System (USCS) w Natural Moisture Content (%) HA -00 Hand Augered upper 6 feet with Static Cone Penetrometer due to potential utility conflict. Depth to Groundwater at Time of Drilling % Passing No. 00 U.S. Standard Sieve * Static Cone Penetrometer was used to measure relative density, values shown on boring logs. DATE BY DESCRIPTION DATE BY DESCRIPTION P. RODNEY MANK, P.E. P.E. NO.: CDM Smith, Inc. SHEET TITLE: Generalized Soil Profiles FL Certificate of Authorization No Western Way, Suite 1, Jacksonville, FL 6 DATE: /8/017 MAE PROJECT NO A PROJECT NAME: JEA Main Street Water Treatment Plant Well Number 1 Jacksonville, Florida FIGURE NO.

17 Appendix A

18 Meskel & Associates Engineering, PLLC FL Certificate of Authorization No Western Way, Suite 1 Jacksonville, FL 6 P: (904) F: (904) PROJECT NAME JEA Main Street Water Treatment Plant Well Number 1 PROJECT LOCATION Jacksonville, Florida CLIENT CDM Smith, Inc. DATE STARTED /9/17 DRILLING CONTRACTOR MAE, LLC COMPLETED /9/17 LATITUDE 'N DRILLING METHOD Standard Penetration Test BORING B-1 PAGE 1 OF 1 PROJECT NO A LONGITUDE 'W LOGGED BY P.R.Young CHECKED BY W. Josh Mele GROUND ELEVATION HAMMER TYPE Automatic DEPTH (ft) 0 SAMPLE DEPTH NUMBER Topsoil (") MATERIAL DESCRIPTION USCS GRAPHIC LOG BLOW COUNTS N-VALUE MOISTURE CONTENT (%) FINES CONTENT (%) ORGANIC CONTENT (%) LIQUID LIMIT PLASTICITY INDEX POCKET PEN. (tsf) RECOVERY % (RQD) REMARKS 1 Loose, Very dark gray fine SAND with silt, few gravel (rock fragments), poorly graded. SP-SM Medium dense, Very pale brown fine SAND, poorly graded. SP NEW MAE LOG LAT/LONG-EOD - NEW TEMPLATE GDT - /10/17 16: - M:\GINT\GINT FILES\PROJECTS\ A\JEA WELL 1.GPJ NOTES Medium dense to loose, Light gray silty fine SAND, poorly graded. Dense, Very pale brown fine SAND with silt, poorly graded. Bottom of borehole at 0 feet. Boring backfilled with soil cuttings. SM SP-SM AT TIME OF DRILLING ft 11 in GROUND WATER LEVELS END OF DAY ---

19 Meskel & Associates Engineering, PLLC FL Certificate of Authorization No Western Way, Suite 1 Jacksonville, FL 6 P: (904) F: (904) PROJECT NAME JEA Main Street Water Treatment Plant Well Number 1 PROJECT LOCATION Jacksonville, Florida CLIENT CDM Smith, Inc. DATE STARTED /9/17 DRILLING CONTRACTOR MAE, LLC COMPLETED /9/17 LATITUDE 0 0.'N DRILLING METHOD Standard Penetration Test BORING B- PAGE 1 OF 1 PROJECT NO A LONGITUDE 'W LOGGED BY P.R.Young CHECKED BY W. Josh Mele GROUND ELEVATION HAMMER TYPE Automatic DEPTH (ft) 0.0 SAMPLE DEPTH NUMBER Topsoil (4") MATERIAL DESCRIPTION AASHTO GRAPHIC LOG BLOW COUNTS N-VALUE MOISTURE CONTENT (%) FINES CONTENT (%) ORGANIC CONTENT (%) LIQUID LIMIT PLASTICITY INDEX POCKET PEN. (tsf) RECOVERY % (RQD) REMARKS 1 Loose, Brown fine SAND with silt, poorly graded. A- 4. Medium dense, Very pale brown fine SAND with silt, poorly graded. A NEW MAE LOG LAT/LONG-EOD - NEW TEMPLATE GDT - /10/17 16: - M:\GINT\GINT FILES\PROJECTS\ A\JEA WELL 1.GPJ NOTES Loose, Light gray fine SAND with silt, poorly graded. Loose, Light gray silty fine SAND, poorly graded. Medium dense, Light gray fine SAND with silt, poorly graded. Bottom of borehole at 10 feet. Boring backfilled with soil cuttings. A- A--4 A AT TIME OF DRILLING 6 ft 0 in GROUND WATER LEVELS END OF DAY ---

20 Meskel & Associates Engineering, PLLC FL Certificate of Authorization No Western Way, Suite 1 Jacksonville, FL 6 P: (904) F: (904) PROJECT NAME JEA Main Street Water Treatment Plant Well Number 1 PROJECT LOCATION Jacksonville, Florida CLIENT CDM Smith, Inc. DATE STARTED /9/17 DRILLING CONTRACTOR MAE, LLC COMPLETED /9/17 LATITUDE 'N DRILLING METHOD Standard Penetration Test BORING B- PAGE 1 OF 1 PROJECT NO A LONGITUDE 'W LOGGED BY P.R.Young CHECKED BY W. Josh Mele GROUND ELEVATION HAMMER TYPE Automatic DEPTH (ft) 0.0. SAMPLE DEPTH NUMBER 1 Asphalt (/4") Limerock Base (6") MATERIAL DESCRIPTION Medium dense, Light yellowish brown fine SAND with silt, poorly graded. Medium dense, Light brownish gray fine SAND with silt, poorly graded. AASHTO A- A- GRAPHIC LOG BLOW COUNTS * N-VALUE MOISTURE CONTENT (%) FINES CONTENT (%) ORGANIC CONTENT (%) LIQUID LIMIT PLASTICITY INDEX POCKET PEN. (tsf) RECOVERY % (RQD) REMARKS * Static Cone Penetrometer 0" - 6" : 0/0" 6" - 1" : 4/6" 1" - 18" : 40/6" 18" - 4" : 1/" 4" - 0" : 9/1" 0" - 6" : /" 6" - 4" : 6/" 4" - 48" : /" 48" - 4" : 41/1" 4" - 60" : 6/" 60" - 66" : /6" 66" - 7" : 6/6" NEW MAE LOG LAT/LONG-EOD - NEW TEMPLATE GDT - /10/17 16: - M:\GINT\GINT FILES\PROJECTS\ A\JEA WELL 1.GPJ NOTES 4 Medium dense, Light gray fine SAND with silt, poorly graded. Loose, Light gray silty fine SAND, poorly graded. Medium dense, Light gray fine SAND with silt, poorly graded. Bottom of borehole at 10 feet. Boring backfilled with soil cuttings and capped with Asphalt Cold Patch. Hand Augered upper 6 feet with Static Cone Penetrometer due to potential utility conflict. A- A--4 A AT TIME OF DRILLING 6 ft 0 in GROUND WATER LEVELS END OF DAY ---

21 KEY TO BORING LOGS USCS/AASHTO Soil Classification Soil classification of samples obtained at the boring locations is based on both the Unified Soil Classification System (USCS) and the American Association of State Highway and Transportation Officials (AASHTO) Classification System. Coarse grained soils have more than 0% of their dry weight retained on a #00 sieve. Their principal descriptors are: sand, cobbles and boulders. Fine grained soils have less than 0% of their dry weight retained on a #00 sieve. They are principally described as clays if they are plastic and silts if they are slightly to non plastic. Major constituents may be added as modifiers and minor constituents may be added according to the relative proportions based on grain size. In addition to gradation, coarse grained soils are defined on the basis of their in place relative density and fine grained soils on the basis of their consistency. Symbol N WOR WOH BORING LOG LEGEND Description Standard Penetration Resistance, the number of blows required to advance a standard spoon sampler 1" when driven by a 140 lb hammer dropping 0". Split Spoon sampler advanced under the weight of the drill rods Split Spoon sampler advanced under the weight of the SPT hammer 0/ Indicates 0 hammer blows drove the split spoon inches; 0 Hammer blows for less than 6 inches of split spoon driving is considered Refusal. (SP) Unified Soil Classification System 00 Fines content, % Passing No. 00 U.S. Standard Sieve w Natural Moisture Content (%) OC Organic Content (%) LL Liquid Limit PI Plasticity Index NP PP Non Plastic Pocket Penetrometer in tons per square foot (tsf) MODIFIERS RELATIVE DENSITY (Coarse Grained Soils) Relative Density N Value * SECONDARY CONSTITUENTS Very Loose Less than (Sand, Silt or Clay) Loose to 8 Trace Less than % Medium Dense 8 to 4 With % to 1% Dense 4 to 40 Sandy, Silty or Clayey 1% to % Very Dense Greater than 40 Very Sandy, Very Silty or Very Clayey % to 0% CONSISTENCY (Fine Grained Soils) ORGANIC CONTENT Consistency N Value * Trace % or less Very Soft Less than 1 Few % to % Soft 1 to Little % to 10% Firm to 6 With Greater than 10% Stiff 6 to 1 Very Stiff 1 to 4 Hard Greater than 4 MINOR COMPONENTS (Shell, Rock, Debris, Roots, etc.) RELATIVE HARDNESS (Limestone) Trace Less than % Relative Hardness N Value * Few % to 10% Soft Less than 0 Little 1% to % Hard Greater than 0 Some 0% to 4% * Using Automatic Hammer KBL USCS Auto

22 FIELD EXPLORATION PROCEDURES Standard Penetration Test (SPT) Borings The Standard Penetration Test (SPT) boring(s) were performed in general accordance with the latest revision of ASTM D 186, Standard Test Method for Standard Penetration Test (SPT) and Split-Barrel Sampling of Soils. The borings were advanced by rotary drilling techniques. A split-barrel sampler was inserted to the borehole bottom and driven 18 to 4 inches into the soil using a 140-pound hammer falling an average of 0 inches per hammer blow. The number of hammer blows for the final 1 inches of penetration (18 sample) or for the sum of the middle 1 inches of penetration (4 sample) is termed the penetration resistance, blow count, or N-value. This value is an index to several in-situ geotechnical properties of the material tested, such as relative density and Young s Modulus. After driving the sampler, it was retrieved from the borehole and representative samples of the material within the split-barrel were containerized and sealed. After completing the drilling operations, the samples for each boring were transported to the laboratory where they were examined by a geotechnical engineer to verify the field descriptions and classify the soil, and to select samples for laboratory testing. Hand Auger Boring The auger boring(s) were performed manually by the use of a hand-held bucket auger in general accordance with the latest revision of ASTM D 14, Standard Practice for Soil Exploration and Sampling by Auger Borings. Representative samples of the soils brought to the ground surface by the auger were placed in sealed containers and transported to our laboratory where they were examined by a geotechnical engineer to verify the field descriptions and classify the soil, and to select samples for laboratory testing. Revised: March 017

23 FIELD EXPLORATION PROCEDURES Static Cone Penetrometer A Static Cone Penetrometer was used to evaluate the consistency or relative density of soils encountered in the soil boring. The penetrometer consists of two rods that are connected to a pressure gauge located at the top of the assembly. The inner rod is independent of the outer sleeve and is fitted with a 60-degree (included angle) conical tip having an area of 1. cm. The penetrometer was advanced six inches into the soil and the reading of total bearing was obtained. Then the penetrometer was slightly retracted in order to return the gauge to a zero reading and then advanced an additional six inches. If refusal of the cone was encountered, the cone was removed and the hole was opened with a hand auger to the depth of refusal to permit continuation of measurements versus depth. At each penetrometer test location, an auger boring was performed to determine the nature of the material corresponding to the penetration depths of the penetrometer. The auger boring was performed manually by the use of a hand-held bucket auger and in general accordance with the latest revision of ASTM D 14, Standard Practice for Soil Exploration and Sampling by Auger Borings. Representative samples of the soils brought to the ground surface by the auger were placed in sealed containers and transported to our laboratory where they were examined by a geotechnical engineer to verify the field descriptions and classify the soil, and to select samples for laboratory testing. Revised: March 017

24 AASHTO Soil Classification System (from AASHTO M 14 or ASTM D 8) General Classification Granular Materials Silt-Clay Materials (% or less passing the 0.07 mm sieve) (>% passing the 0.07 mm sieve) A-1 Group Classification A-1-a A- A-1-b A- A-7 A-4 A- A-6 A-7-* A-7-6* A--4 A-- A--6 A--7 Sieve Analysis, % passing:.00 mm (No. 10) 0 max 0.4 (No. 40) 0 max 0 max 1 min 0.07 (No. 00) 1 max max 10 max max max max max 6 min 6 min 6 min 6 min 40 max 41 min 40 max 41 min 40 max 41 min 10 max 10 max 11 min 11 min 10 max 10 max 11 min 11 min Characteristics of fraction passing 0.4 mm (No. 40): Liquid Limit Plasticity Index Usual types of significant constituent materials General local** rating as a subgrade 6 max N.P. stone fragments, gravel and sand fine sand excellent to good 40 max 41 min silty or clayey gravel and sand silty soils clayey soils fair to poor * Plasticity index of A-7- subgroup is equal to or less than the LL - 0. Plasticity index of A-7-6 subgroup is greater than LL 0 ** Northeast Florida

25 Unified Soil Classification System (USCS) (from ASTM D 487) Group Symbol Major Divisions Coarse-Grained Soils More than 0% retained on the 0.07 mm (No. 00) sieve Gravels 0% or more of coarse fraction retained on the 4.7 mm (No. 4) sieve Clean Gravels GW Well-graded gravels and gravel-sand mixtures, little or no fines GP Poorly graded gravels and gravel-sand mixtures, little or no fines Gravels with Fines GM Silty gravels, gravel-sand-silt mixtures GC Clayey gravels, gravel-sand-clay mixtures Sands 0% or more of coarse fraction passes the 4.7 (No. 4) sieve Clean Sands SW Well-graded sands and gravelly sands, little or no fines SP Poorly graded sands and gravelly sands, little or no fines Sands with Fines SM Silty sands, sand-silt mixtures SC Clayey sands, sand-clay mixtures ML Inorganic silts, very fine sands, rock four, silty or clayey fine sands CL Inorganic clays of low to medium plasticity, gravelly/sandy/silty/lean clays OL Organic silts and organic silty clays of low plasticity MH Inorganic silts, micaceous or diatomaceous fine sands or silts, elastic silts CH Inorganic clays or high plasticity, fat clays OH Organic clays of medium to high plasticity PT Peat, muck, and other highly organic soils Silts and Clays Liquid Limit 0% or less Fine-Grained Soils More than 0% passes the 0.07 mm (No. 00) sieve Silts and Clays Liquid Limit greater than 0% Highly Organic Soils Typical Names Prefix: G = Gravel, S = Sand, M = Silt, C = Clay, O = Organic Suffix: W = Well Graded, P = Poorly Graded, M = Silty, L = Clay, LL < 0%, H = Clay, LL > 0%