S01_0001_Geotechnical Engineering Report.pdf

GEOTECHNICAL ENGINEERING REPORT

NRCS PMC BUILDING RENOVATIONS

438 AIRPORT ROAD

GALLIANO, LOUISIANA

NOLAGEO FILE NO. 17-003

PREPARED FOR

PEREZ ARCHITECTS

2525 BURGUNDY STREET

NEW ORLEANS, LOUISIANA 70117

JANUARY 15, 2018

BY

NOLAGEO LLC

727 SAINT ROCH AVENUE

NEW ORLEANS, LOUISIANA 70117

504-952-6652

TABLE OF CONTENTS

1. PROJECT INFORMATION

1.1 PROJECT AUTHORIZATION

1.2 PROJECT DESCRIPTION

1.3 PURPOSE AND SCOPE OF SERVICES

2. SITE AND SUBSURFACE CONDITIONS

2.1 SITE DESCRIPTION

2.2 FIELD EXPLORATION

2.3 SUBSURFACE CONDITIONS

2.4 GROUNDWATER CONDITIONS

2.5 IBC SITE CLASSIFICATION

3. ENGINEERING ANALYSES AND RECOMMENDATIONS

3.1 FOUNDATION CONSIDERATIONS

3.2 GENERAL SITE PREPARATION

3.3 FILL MATERIALS

3.4 FILL PLACEMENT AND COMPACTION

3.5 ESTIMATED PILE LOAD CAPACITIES

3.6 PILE SETTLEMENT

3.7 GROUP EFFECT

3.8 DEEP FOUNDATION INSTALLATION

3.9 PILE DRIVING MONITORING

3.10 VIBRATION MONITORING

3.11 PILE LOAD TESTING

3.12 PAVEMENT IMPROVEMENT

4. GENERAL CONSTRUCTION CONSIDERATIONS

4.1 MOISTURE SENSITIVE SOILS/WEATHER RELATED CONCERNS

4.2 DRAINAGE AND GROUNDWATER CONCERNS

4.3 SHALLOW EXCAVATIONS

4.4 PAVEMENT CONSTRUCTION

5. REPORT LIMITATIONS

Figures

Figure 1 Project Location Map

Figure 2 CPTu Sounding Location Plan

Figure 3 Geological Cross Section

Appendix

CPTu Sounding Logs

1. PROJECT INFORMATION

1.1 Project Authorization

NOLAGEO has completed a geotechnical engineering study for the proposed National Resources Conservation Service (NRCS) Plant Materials Center (PMC) building in Golden Meadow adjacent to the town of Galliano, Louisiana. This study was accomplished in general accordance with NOLAGEO Proposal No. 17-003 dated September 13, 2017. Authorization to proceed was given via an email dated November 16, 2017. This report presents the results of our field exploration, foundation recommendations, and general site preparation and construction guidelines.

1.2 Project Description

Project information was provided by Mr. Mark Clayton with Perez and Mssrs. Jonathan Sofranko, P.E. and Greg Eckert, P.E. with Morphy Makofsky, Inc. (MMI). The information included general project information and a site plan figure including exploration locations and depth suggestions.

Based on the furnished information NOLAGEO understands that the project consists of renovations to an existing building and adding two power generators on concrete pads at locations depicted on the figure shared by MMI. It is our understanding that any fill added to the site will not exceed 2 feet in height. MMI also indicated that the structural loads will not exceed 15 tons.

The geotechnical recommendations presented in this report are based on the available project information, structure location, and the subsurface materials described in this report. If any of the noted information is incorrect or has changed, please inform NOLAGEO in writing so that we may amend the recommendations presented in this report if appropriate and if desired by the client. NOLAGEO will not be responsible for the implementation of its recommendations in case we are not be notified of changes to the project.

1.3 Purpose and Scope of Services

The purpose of this study is to evaluate the subsurface conditions at the site and provide geotechnical recommendations for the proposed construction. The achieve this goal, the scope of services consisted of performing two (2) cone penetrometer soundings with pore pressure measurements (CPTu) and prepare a geotechnical report detailing our findings. Specifically, this report provides available project information, outlines the exploration procedures, describes the site subsurface conditions, and presents results of the geotechnical engineering analyses regarding foundation recommendations, fill placement, and pavement improvement. The report also provides general site preparation and pavement construction considerations.

The scope of geotechnical services did not include an environmental assessment for determining the presence or absence of wetlands, or hazardous or toxic materials in the soil, surface water, groundwater, or air on or below, or around this site. Any statements in this report or on the boring logs regarding odors, colors, and unusual or suspicious items or conditions are strictly for information purposes. Prior to development of this site, an environmental assessment is advisable.

2. SITE AND SUBSURFACE CONDITIONS

2.1 Site Description

The planned project site is located at the NRCS’ PMC in Golden Meadow, which is adjacent to the town of Galliano in Lafourche Parish, Louisiana. Specifically, the site is located at 438 Airport Road in Galliano at its intersection with Apache Road and approximately 1.6 miles northeast of its intersection with Highway 308. Based on satellite imagery, several buildings are located at the site with what appears to be limestone parking lots. The site is bound to the east by a drainage canal and the South Lafourche Leonard Miller Jr. Airport and to the west, north, and south by agricultural land. A Project Location Map is presented as Figure 1.

2.2 Field Exploration

Two (2) CPTu’s, designated CPTu-1 and CPTu-2, were performed for this project. The scope and extent of the field exploration was specified by NOLAGEO and MMI. Both CPTu’s were performed to a depth of approximately 70 feet. A CPTu Sounding Plan is included as Figure 2.

The soundings were located and marked in the field by NOLAGEO based on information presented by MMI. The soundings were accomplished in general accordance with ASTM Standard Procedures. The CPTu soundings consisted of pushing a 1.5-inch diameter instrumented cone at a constant rate of 2 centimeters per second using an enclosed truck-mounted hydraulic press. Electronic sensors in the cone continuously measures and record tip resistance, sleeve resistance, friction ratio, and pore water pressure and depth as the cone is pushed into the ground. No actual soil samples were obtained during a CPTu sounding; instead, the measured values were correlated to obtain design parameters including soil strength, normalized standard behavior charts (soil classification), and various other geotechnical parameters using state-of-the-art interpretation software. Selected results are included in charts on sounding logs. The sounding logs are appended to this report.

2.3 Subsurface Conditions

Reference to the logs of soundings CPTu-1 and CPTu-2 shows approximately 2 feet of desiccated sandy and clayey Fill or Top Soil immediately underneath the existing ground surface. The surface layer is underlain by 7 to 9 feet of very soft Fat Clay (CH) or Lean Clay (CL) layers followed by a 2 feet of very loose Sand (SP) to Silty Sand (SM). Soft Fat Clay (CH) or Lean Clay (CL) layers were then encountered to the 32- to 34-foot depth. A 12-foot thick layer of medium dense Sand (SP) to Silty Sand (SM) that gradually becomes denser was then present followed by firm to stiff Fat Clay (CH) or Lean Clay (CL) layers to the exploration’s termination depth of approximately 70 feet.

Table 1 summarizes the general major stratification of the subsurface soils encountered at the soil boring and CPTu sounding exploration locations throughout the site. A representative geological cross section is shown on Figure 3.

TABLE 1 - GENERAL MAJOR SUBSOIL STRATIFICATION

Stratum Average Boundary

Depth (feet) Average

Thickness (feet) Subsoil Description

Top Bottom

І 0 2 2 Desiccated Fill or Top Soil

II 2 9-11 8

Very Soft to Soft Fat Clay (CH) and Lean Clay (CL)

III 9-11 12-14 2

Very Loose Sand (SP) to Silty Sand

(SM)

IV 12-14 32-34 20 Soft Fat Clay (CH) and Lean Clay (CL)

V 32-34 43-45 12 Medium Dense to Dense Sand (SP) to Silty Sand (SM)

VI 70 TD --

Firm to Stiff Fat Clay (CH) or Lean Clay

(CL)

Note: The subsurface description given herein is of a generalized nature and intended to highlight the major subsurface stratification features and material character. The CPTu sounding logs (found in the Appendix) should be reviewed for specific information at the specific locations. These records also include soil description, stratification, penetration resistances, and locations of the samples and laboratory test data.

The stratifications shown on the sounding logs represent the conditions only at the specific sounding location. Variations may occur and should be expected between the locations of the soundings and represent the approximate boundaries between the major subsurface materials at the exploration locations as the actual stratum transition may vary throughout the site. Water level information interpreted from the obtained data is also shown on the sounding.

2.4 Groundwater Conditions

Free groundwater below the existing ground surface was estimated at both sounding locations using pore water pressure data to be at a depth of approximately 4 feet below the existing ground surface. The groundwater levels presented in this report are those that were estimated using the available data at the time of our field activities. Groundwater could fluctuate due to seasonal precipitation and variations in weather conditions. It is recommended that the Contractor determine the actual groundwater levels in the area the during construction activities.

2.5 IBC Site Classification

For purposes of seismic design, a site Class E as defined in Table 1613.5.2 in the 2009 International Building Code (IBC) is recommended for use at this site. The site class is based on the subsurface conditions encountered at our soil borings, the results of field data and laboratory testing, and our experience with similar projects in this area. It should be noted that our deepest soil boring extended to 70 feet and that the IBC classifications are based on the upper 100 feet of the soil profile.

3. ENGINEERING ANALYSES AND RECOMMENDATIONS

3.1 Foundation Considerations

The type and depth of a foundation suitable for a given structure primarily depends on several factors including subsurface conditions, the function of the structure, the loads it may carry, the cost of the foundation, and the criteria set by the MMI with respect to vertical and differential movement that the structure can withstand without damage.

Data from the logs of soundings CPTu-1 and CPTu-2 indicate that the near-surface soils underlying the site are desiccated and dry. However, these soils will become very weak when wet, at which point they will become susceptible to vertical and differential settlement due to the stress influence applied by a shallow foundation system. Consequently, consideration was given to using small or large timber piles to support the proposed structures. Details related to general site preparation, structural fill placement, foundation recommendations, pavement improvement guidelines, and general and pavement construction considerations are presented in the following sections.

3.2 General Site Preparation

According to furnished information any added fill will not exceed 2 feet in height and would most likely replace existing near-surface materials. No placement and compaction provisions apply to the fill to be placed within the footprint of the concrete slabs since they will be supported on piles. Non-engineered fill outside the pile supported areas should be avoided. Fill in pavement areas should be placed and compacted as recommended in this report.

It is our opinion that methods, means, and sequence of construction including site preparation should be the responsibility of the project contractor who should be specialized in this type of construction. However, some geotechnical related considerations are given herein for guidance.

Site preparation should include the removal of existing pavement, existing fill, and, possibly, some organic clay and deleterious materials from the construction area. The actual depth of stripping beneath the existing or new pavement areas should be determined by a representative of the Geotechnical Engineer at the time of construction. However, our preliminary recommendation is that the upper 12 to 24 inches of desiccated soil and other deleterious materials throughout the construction area be removed. Voids left by removal of any deleterious materials or construction debris in the pavement area should be backfilled with properly compacted structural fill. Any existing utility lines should be located and re-routed, as necessary.

3.3 Fill Materials

The structural fill to be used at the site should consist of locally available “pumped” river sand having less than 10 percent fines passing the No. 200 sieve. Alternatively, select fill consisting of either silty or sandy clay with a Plasticity Index between 10 and 20 and a Liquid Limit less than 40 is also recommended. The fill material shall be free of roots, debris, or organic matter, clay lumps and other deleterious materials.

The fill materials within the pile-supported area should be selected and placed so that it does not present high resistance to pile driving. Consequently, a lower degree of compaction within the perimeter of pile-supported structures should be considered. The fill in the pavement improvement areas should be placed and compacted as discussed in the next section.

3.4 Fill Placement and Compaction

Prior to placement of fill, a non-woven geotextile fabric such as Mirafi 17N or equivalent should be spread over the well-drained, stripped, and prepared subgrade surface. The first layer should be placed in a relatively uniform horizontal lift and be adequately keyed into the stripped and scarified subgrade soils.

The fill placed in pavement areas should be placed in maximum lifts of 8 inches of loose material and should be compacted to 95% percent of its maximum dry density within the range of plus or minus three (± 3) percentage points of the optimum moisture content value as determined by a Standard Proctor compaction test (ASTM D698). Each lift of compacted structural fill should be tested by a representative of the Geotechnical Engineer prior to placement of subsequent lifts.

As a guideline, field density tests should be taken at a frequency of not less than one test per lift for every 5,000 square feet in the parking/drive areas. Adequate drainage must be provided prior to and during site work. The area of the proposed construction should be graded to promote rapid runoff.

3.5 Estimated Pile Load Capacities

A deep foundation system was evaluated for support of the proposed structures based on the field exploration data obtained from the CPTu soundings and furnished design information.

Following discussions with Mr. Sofranko, consideration was given to Class B (7”-tip – 12” butt) and small Class 5 (6” tip – 8” butt) timber piles. The groundwater was measured at approximately 4 feet below the existing ground surface and may become deeper or shallower during the design life of the structure(s), which indicates that the timber piles could be partially submerged possibly for extended periods of time. Therefore, treated timber piles are recommended for this project.

It is also our opinion that should timber piles need to be driven through the bottom of Stratum V then pre-drilling through the bottom 5 feet of the stratum could be required as the sand becomes denser.

The piles will generally derive their support through skin friction along their embedded lengths with negligible contribution in this case from tip resistance. Lengths given are measured from the existing ground surface within the area explored. However, a cutoff of up to 2 feet should have no effect on the estimated capacities and any additional length needed above their reference elevation to accommodate new fill should be added to the tabulated lengths. The allowable capacities of treated timber piles at the locations of CPTu-1 and CPTu-2 are presented in Tables 2 and 3, respectively.

TABLE 2 – Allowable Single Pile Capacity in Tons1 - CPTu-1 Location (Factor of Safety = 2.0 for Compression, Factor of Safety = 3.0 for Tension)

Pile Tip Penetration2

(feet)

Class 5 6” Tip – 8” Butt Treated Timber Piles

Class “B” 7” Tip – 12” Butt Treated Timber Pile

Compression3 Tension Compression Tension

35 8 4 9 4 ½

40 (Sand) 14 6 ½ 16 7 ½

45 12 8 14 9

50 -- -- 15 ½ 10

55 -- -- 17 11

60 -- -- 18 12

65 -- -- 20 13 ½

TABLE 3 – Allowable Single Pile Capacity in Tons1 - CPTu-2 Location (Factor of Safety = 2.0 for Compression, Factor of Safety = 3.0 for Tension)

Pile Tip Penetration2

(feet)

Class 5 6” Tip – 8” Butt Treated Timber Piles

Class “B” 7” Tip – 12” Butt Treated Timber Pile

Compression3 Tension Compression Tension

35 7 ½ 3 ½ 8 ½

40 (Sand) 10 5 ½ 11 ½

45 (Sand) 12 ½ 8 14

50 -- -- 17

55 -- -- 18

60 -- -- 20

65 -- -- 21

1. These are allowable soil-pile related capacities and consideration should be given to the structural integrity of the pile member.

2. Pile tip penetration below existing ground surface at the exploration locations.

3. Spliced timber piles are not recommended for support of tension or lateral loads.

The forgoing pile capacities include a factors of safety (FS) of 2.0 and 3.0 against failure in compression and tension, respectively. However, lower safety factors could be considered if design loads already contain some safety factors and/or if the loads are transient and of relatively short duration.

3.6 Pile Settlement

No detailed settlement analyses were made since deep foundation type, size, layout, etc. are not known now. Settlement of pile-supported foundations using the recommended pile or load capacities in single widely spaced rows or in clusters of up to six (6) or eight (8) piles is estimated to be on the order of ¾ to 1 inch. Settlement would increase with the size of the pile cluster.

3.7 Group Effect

The effect of pile grouping on the single pile or load capacities is dependent on pile spacing, pile length and soil characteristics throughout the pile length and below the pile tips. Assuming a minimum center to center spacing of 3 ft., group effect should be unimportant for pile clusters of less than 6 piles. Group effect could become important for larger clusters and should be evaluated when actual pile layouts are known.

As per the New Orleans Amendment to Chapter 18 of the International Building Code (IBC), latest edition, the minimum center-to-center spacing for all piles should be either three (3) feet, three

(3) times the pile diameter or width, or as determined by the following expression (whichever is greater):

SPAC = 0.05 (L1) + 0.025 (L2) + 0.0125 (L3)

Where:

SPAC = Center-to-center spacing of piles in ft L1 = Pile penetration up to 100 ft L2 = Pile penetration from 101 to 200 ft L3 = Pile penetration beyond 201 ft

The allowable load-carrying capacity of a pile group is expressed by the following equation:

Qa = (P L C) + [2.6qu (1 + 0.2 w/b)]

FSF FSB

Where:

Qa = allowable load-carrying capacity of the pile group, lb P = perimeter distance of the pile group, ft L = pile length, ft C = average (weighted) cohesion or shear strength between ground surface and the depth of the pile tip, ft Qu = average confined compressive strength of the material in the zone below the pile tips, psf

3.8 Deep Foundation Installation

Pile driving hammers used to drive timber piles should be selected according to pile type, length, size, and weight of pile, as well as potential vibrations expected during pile driving operations.

Care should be taken to assure that the selected hammer is capable of achieving the desired penetration without causing damage to the piles or excessive vibrations which could damage existing, nearby structures. Generally, the experience of local contractors is often the primary source for the selection of the hammer. The suitability of a given hammer to install the project piles should be confirmed using a Wave Equation Analysis (WEAP) or similar software. The

WEAP analysis should provide a representative simulation of the suitability of the proposed driving system for installing the selected piles. The WEAP analysis to be prepared by the contractor should be submitted for review and approval by the Geotechnical Engineer.

In general, driving of small timber piles should be limited to the rate of 10 to 12 blows per foot using a Vulcan No. 2 hammer or a 2000 to 3000 lb drop hammer falling 5 ft. For Class “B” timber piles (7” Tip – 12” Butt), hammers having a rated energy in the range of 15,000 to 20,000 foot-pounds are recommended. Driving of these piles should be limited to the rate of 25 blow per foot.

These recommendations are given to reduce possible damage to the piles. Each pile should be driven to the desired tip penetration, and driving resistance should be monitored without interruption of the driving operations.

Driving of the center piles in the cluster first will better facilitate driving operations. Accurate records of the final tip elevation and driving resistances should be obtained during the pile driving operations. Some pile heaving may have been experienced during installation of adjacent displacement type piles. It is therefore recommended that the butt elevation of the piles be recorded and if significant heave is noted after driving of subsequent piles, provisions must be made for reseating them.

3.9 Pile Driving Monitoring

We recommend that the pile driving be monitored by the Geotechnical Engineer. Occasionally, premature “refusal” could occur due to poor hammer performance rather than soil resistance.

Any changes in hammer blow counts should be carefully examined before making any decisions pile penetration or integrity. For example, a sudden drop in blow counts resistance could an indicator of a broken pile.

3.10 Vibration Monitoring

Piles for this project will be driven in relative close proximity to existing buildings. Consequently, vibrations due to pile driving could induce cracking in these structures. Thresholds of vibration-induced cracking are generally site specific and depend on the type and age of the structure, the frequency of ground vibration, and the type of soil supporting the structure. Research by the U.S.

Bureau of Mines (USBM) and other investigative groups have established criteria relating the occurrence of structural damage to certain frequencies and level of ground motion. According to the USBM, within the range of four (4) to twelve (12) hertz, the maximum particle velocity recommended to preclude the threshold damage to plaster-on-wood for old structures is 0.5 inch per second (ips). A threshold of 0.25 ips has been adopted by the local engineering community and hence it is recommended for the project.

3.11 Pile Load Testing

It is recommended that pile capacities be verified by static pile load testing performed in accordance with ASTM D1143 on at least one (1) pile. The installation of the test and production piles should be logged and monitored by a qualified testing laboratory.

3.12 Pavement Improvement

The performance of pavements depends upon several factors including (1) the characteristics of the supporting soils; (2) the magnitude and frequency of wheel load applications; (3) quality of construction materials; (4) the contractor’s placement and workmanship abilities; and (5) the desired design life. We evaluated both flexible and rigid pavement options for this project.

Detailed grading information was not available at the time this report was prepared. However, it is anticipated that less than two (2) feet of fill will be required in the pavement areas to achieve design grades. The traffic is anticipated to consist of passenger cars, light-duty trucks and occasional heavy-duty trucks.

Our scope of services did not include extensive sampling for determination of Coefficient of Subgrade Reaction (K) value and California Bearing Ratio (CBR) of existing subgrade or potential sources of imported fill for the specific purpose of a detailed pavement analysis. Instead, we have performed the analysis using the pavement related design parameters presented in Table 4 that are typical for the area soil types and based on the data from the CPTu soundings. For our analysis, a California Bearing Ratio (CBR) of three (3) and a modulus of subgrade reaction (k) of 125 pci have been assigned for the near surface soils.

Table 4 – Pavement Design Parameters

Parameter Value

CBR 3

Modulus of Subgrade Reaction, k 125 pci

Concrete Elastic Modulus 3.6 x 106 psi

Concrete Modulus of Rupture 650 psi

Reliability 85%

Deviation

0.45 – Flexible

0.35 – Rigid

Initial Serviceability 4.2

Terminal Serviceability 2.0

Load Transfer 3.2

Drainage Coefficient 1.0

Design Life 20 years

Layer Coefficients Asphalt Wearing Course 0.41

Limestone Base 0.14

Equivalent Single Axle Loads (ESALs) 35,000 – Light Duty

220,000 – Heavy Duty

The recommended pavement sections are presented in Table 5 and are considered typical and minimum for the above design parameters in the general site area and anticipated traffic condition. We understand that budgetary considerations sometimes warrant thinner pavement sections than those presented. However, the owner, and the project designers should be aware that thinner pavement sections may result in increased maintenance costs and lower than anticipated pavement life. The pavement subgrade should be prepared as discussed in the site preparation section of this report. Based on the above parameters, the following flexible and rigid pavement sections are recommended:

Table 5 – Recommended Pavement Sections

FLEXIBLE PAVEMENT

Pavement Materials Minimum Thickness, inches

Light Duty(1) Heavy Duty(2)

Asphaltic Concrete Wearing Course 3 4

Compacted Limestone Base 6 8

Compacted Structural Fill 12 12

RIGID PAVEMENT

Pavement Materials` Minimum Thickness, inches

Light Duty(1) Heavy Duty(2)

Portland Cement Concrete 5 6

Compacted Structural Fill 12 12

4. GENERAL CONSTRUCTION CONSIDERATIONS

It is our opinion that methods, means and sequence of the proposed construction should be the responsibility of the project Contractor who should be specialized in this type of construction.

However, some general geotechnical considerations are given herein for general guidance, but it is the responsibility of the Contractor to identify and select the most appropriate construction methods, means and sequence needed to meet the specific project requirements, specifications and schedule.

It is recommended that NOLAGEO be retained to provide observation and testing of construction activities (QC or QA) related to this project. NOLAGEO cannot accept any responsibility for any conditions which deviate from those described in this report, nor for the performance of the foundations if not engaged to also provide construction observation and testing for this project.

4.1 Moisture Sensitive Soils/Weather Related Concerns

The upper soils encountered at this site were desiccated and dry at the time of the field exploration. However, these soils will quickly turn soft should they become wet and will be slow to dry and thus significantly slow the progress of grading and compaction activities. It will, therefore, be advantageous to perform earthwork activities during dry weather and once good drainage has been established within the construction area. In this regard, collection, drainage and disposal of rainwater runoff should be established and maintained by the Contractor prior to, during and after construction, as will be discussed.

4.2 Drainage and Groundwater Concerns

Good drainage, both during and after construction, should be provided to divert the flow of surface water away from the construction area. Moreover, the site is adjacent to a drainage canal, which could influence the depth of the water table underlying the site. Groundwater was at the site was estimated to be at the 4-foot depth below the existing ground surface (refer to Section 2.4). Seasonal variations will cause fluctuations of the water table or a perched water table to be present in the upper soils. Any water accumulation should be removed from excavations by pumping. The geotechnical engineer should be consulted should excessive and uncontrolled amounts of seepage occur.

4.3 Shallow Excavations

In Federal Register, Volume 54, No. 209 (October 1989), the United States Department of Labor, Occupational Safety and Health Administration (OSHA) amended its “Construction Standards for Excavations, 29 CFR, part 1926, Subpart P”. This document was issued to better insure the safety of workmen entering trenches or excavations. It is mandated by this federal regulation that excavations, whether they be utility trenches, basement excavation or footing excavations, be constructed in accordance with the new OSHA guidelines. It is our understanding that these regulations are being strictly enforced and if they are not closely followed, the owner and the contractor could be liable for substantial penalties.

The contractor is solely responsible for designing and constructing stable, temporary excavations and should shore, slope, or bench the sides of the excavations as required to maintain stability of both the excavation sides and bottom. The Contractor’s “responsible person”, as defined in 29 CFR Part 1926, should evaluate the soil exposed in the excavations as part of the contractor’s safety procedures. In no case should slope height, slope inclination, or excavation depth, including utility trench excavation depth, exceed those specified in local, state, and federal safety regulations.

4.4 Pavement Construction

The importance of good drainage cannot be over-emphasized during pavement construction.

Proper site drainage should be maintained at all times and construction of the pavement should only take place when the subgrade is dry and stable. Providing drainage during construction will reduce the potential for “pumping”, which inhibits proper compaction of the rigid pavement base of the flexible pavement subbase. Should pumping be observed, the affected areas should be stripped and replaced with pavement base or subbase. Alternatively, soils that rut or pump excessively could be lime-stabilized. NOLAGEO can perform a lime stabilization test upon request.

It is our opinion that the methods, means, and sequence of constructions of the pavement improvement are the responsibility of the contractor, who should be experienced in this type of construction. It should be noted that the geotechnical recommendations presented in this report regarding pavement section thickness are based on assumed traffic conditions presented in Table

5. However, it should be noted that the fully or partially constructed pavement improvement may be subjected to heavier construction equipment such as bulldozers, spreaders, rollers, concrete trucks, dump trucks, etc. Therefore, appropriate measures should be taken by the contractor in terms of site preparation, base and subbase compaction, selection of paving equipment, etc. to assure the performance of the pavement improvement during and after construction.

5. REPORT LIMITATIONS

The recommendations submitted in this report are based on the available subsurface information obtained by NOLAGEO and design details furnished by client representatives. If there are any revisions to the plans for this project, or if deviations from the subsurface conditions noted in this report are encountered during construction, NOLAGEO should be notified immediately to determine if changes in the foundation recommendations are required. If NOLAGEO is not notified of such changes, NOLAGEO will not be responsible for the impact of those changes on the project.

The geotechnical engineer warrants that the findings, recommendations, specifications, or professional advice contained herein have been made in accordance with generally accepted professional geotechnical engineering practices in the local area. No other warranties are implied or expressed.

After the plans and specifications are more complete, the geotechnical engineer should be retained and provided the opportunity to review the final design plans and specifications to check that our engineering recommendations have been properly incorporated into the design documents. At that time, it may be necessary to submit supplementary recommendations. If NOLAGEO is not retained to perform these functions, NOLAGEO will not be responsible for the impact of those conditions on the project. This report has been prepared for the exclusive use of Perez for the specific application to the proposed NRCS PMC Building renovations in Galliano, Louisiana.

We are providing this information solely as a service to our client. NOLAGEO does not assume responsibility for construction site safety or the Contractor’s or other parties’ compliance with local, state, and federal safety or other regulations.

Date: 01/11/2018 By: ZHA

PROJECT LOCATION MAPNOLAGEO LLC

Geotechnical Engineers

Galliano

New Orleans

Galliano

Figure 1

CPTu-2

By: ZHA

NOLAGEO LLC

Geotechnical Engineers

CPTu SOUNDING PLAN

CPTu-1

Figure 2

CPTu-2

By: ZHA

NOLAGEO LLC

Geotechnical Engineers

GEOLOGICAL CROSS SECTION

CPTu-1

Figure 3

APPENDIX

CPTu Sounding Logs

Project: NRCS PMC Renovations

NOLAGEO LLC

Geotechnical Engineers

New Orleans, LA http://www.nolageo.com

Total depth: 70.21 ft, Date: 12/22/2017

Surface Elevation: 1.00 ft

Golden Meadows/Galliano, LA

Coords: X:75.00, Y:175.00

Cone Type:

Cone Operator: JJP - Ardaman & Associates

CPT: CPT-1

Location:

CPeT-IT v.2.0.2.5 - CPTU data presentation & interpretation software - Report created on: 1/11/2018, 9:00:10 PM 1

Project file: C:\Users\Ziad\Documents\NOLAGEO\NRCS Project\Pile Capacity\Pile Capacity 2.cpt

Project: NRCS PMC Renovations

NOLAGEO LLC

Geotechnical Engineers

New Orleans, LA http://www.nolageo.com

Total depth: 71.06 ft, Date: 12/20/2017

Surface Elevation: 1.00 ft

Golden Meadows/Galliano, LA

Coords: X:175.00, Y:175.00

Cone Type: Uknown

Cone Operator: JJP - Ardaman & Associates, Inc.

CPT: CPT-2

Location:

CPeT-IT v.2.0.2.5 - CPTU data presentation & interpretation software - Report created on: 1/11/2018, 9:16:32 PM 1

Project file: C:\Users\Ziad\Documents\NOLAGEO\NRCS Project\Pile Capacity\Pile Capacity 2.cpt