A2 - SOW Rollinson-HFC and SL-BFS 01MAR25.pdf

STATEMENT OF WORK

Hatteras Ferry-Rollinson Channel and Big Foot Slough Channel-Silver Lake Harbor 2025 Subsurface Investigation and Geotechnical Laboratory Testing

Dare and Hyde Counties, North Carolina

18 February 2025

01 March 2025

I. GENERAL REQUIREMENTS

General.

The Contractor shall furnish all services, labor, equipment, supplies, tools and incidentals necessary to perform vibracore sampling, development of drilling logs, laboratory testing of soils, and other services as specified herein. A total of 71 x vibracores are to be drilled for two navigation channel projects, Hatteras Ferry-Rollinson Channel located in Dare County, NC and Big Foot Slough-Silver Lake Harbor in Hyde County, NC (Figures 1 and 2). The Contractor shall complete the Priority of effort is 1) Hatteras

Ferry-Rollinson Channel, then 2) Big Foot Slough-Silver Lake Harbor. The work for the Hatteras Ferry-

Rollinson Channel shall be completed within 60 days of contract award. All other work shall be completed within 180 days of calendar award.

A total of 36 x vibracore are to be drilled within proposed navigation corridors located in the vicinity of

Hatteras Ferry Channel and Rollinson Channel (Figures 1, 3, and 4). Within the investigation area, the bathymetry ranges from about 0 ft. to -15 ft. MLLW and greater. The vibracore coordinates for borings located within Rollinson-Hatteras Ferry Channel are found in Table 1. Hatteras Ferry-Rollinson Channel is the priority effort shall be completed first.

A total of 35 x vibracore are to be drilled within proposed navigation corridors located in the vicinity of

Silver Lake Harbor and Big Foot Slough Channel (Figures 2, 5, and 6). Within the investigation area, the bathymetry ranges from about 0 ft. to -15 ft. MLLW and greater. The vibracore coordinates for borings located within Rollinson-Hatteras Ferry Channel are found in Table 2. Big Foot Slough-Silver Lake Harbor is the second effort.

The vibracores shall be drilled in 10- and 20-foot lengths as shown in Figures 1-6. The maximum project depth for the proposed navigation corridors is -14 feet MLLW. If the vibracores penetrate deeper than

-14 MLLW, the cored sediments will still be visually classified, photographed, and may be tested. The results from this subsurface investigation will be utilized to identify the material characteristics to gain environmental clearance for modification of the navigation corridor. Characterization of the shoals is required to identify the most appropriate dredged material disposal strategy.

Responsibility

The Contractor shall furnish qualified personnel to ensure the accomplishment of work specified in this SOW. Additionally, the Contractor shall furnish all services, equipment, personnel, and travel required in connection with this SOW. The Contractor is responsible for maintaining the submittal timeline outlined in Table 3

Table 2. Big Foot Slough Channel-Silver Lake Harbor, Vibracore name, coordinates, and length of tube.

Vibracore Northing Easting Tube Length (ft)

BFS-25-V-001 2892932.3 525525.1 10

BFS-25-V-002 2892443.4 524420.5 10

BFS-25-V-003 2893418.0 524633.9 10

BFS-25-V-004 2892793.1 523770.8 20

BFS-25-V-005 2893838.6 523705.0 20

BFS-25-V-006 2893138.1 522702.8 20

BFS-25-V-007 2894218.0 522966.4 20

BFS-25-V-008 2893711.2 521888.4 20

BFS-25-V-009 2894548.5 522003.4 20

BFS-25-V-010 2894247.3 521056.5 20

BFS-25-V-011 2893949.9 520439.5 20

BFS-25-V-012 2894591.4 520271.4 20

BFS-25-V-013 2894888.9 519026.1 20

BFS-25-V-014 2895516.4 512747.5 20

BFS-25-V-015 2895284.6 514414.2 20

BFS-25-V-016 2894693.9 513638.1 10

BFS-25-V-017 2894214.7 514417.7 20

BFS-25-V-018 2894683.5 515205.0 20

BFS-25-V-019 2893164.5 514317.5 20

BFS-25-V-020 2893663.1 516036.6 20

BFS-25-V-021 2892785.6 516496.1 20

BFS-25-V-022 2891603.7 515235.9 20

BFS-25-V-023 2889965.6 516215.7 10

BFS-25-V-024 2888721.0 517867.2 10

BFS-25-V-025 2887925.9 517082.8 20

BFS-25-V-026 2887245.0 518463.2 20

BFS-25-V-027 2886450.0 517474.5 10

BFS-25-V-028 2886281.6 518841.3 20

BFS-25-V-029 2885034.2 518025.3 10

BFS-25-V-030 2884695.7 519315.5 10

BFS-25-V-031 2883485.0 518378.7 10

BFS-25-V-032 2883446.9 519968.3 10

BFS-25-V-033 2881694.3 518883.7 10

BFS-25-V-034 2881921.4 520370.8 10

BFS-25-V-035 2880365.1 519377.1 10

Table .

Direction

The Contractor shall accept directions only from the Wilmington District Contracting Officer (KO), Mrs.

Rosalind Shoemaker (910-251-4436) or her designee. Requests or desires of the Users, Using Agency, or any other party made directly to the Contractor shall be immediately brought to the attention of the

KO for this Contract. Any changes to this SOW must be authorized in writing by the KO.

Coordination

The COR is Mr. Stephen Fabian, P.G. (910‐251‐4029) and he shall be the Contractor’s point of contact (POC) for all submittals and timeline execution. The technical point of contact is Mr. Kelley Kaltenbach, P.G. (910-228-9845). At least one meeting between the Contractor’s project manager and Wilmington

District personnel shall be performed weekly to discuss the Contractor’s progress and Wilmington

District’s technical review of submittals.

The Contractor shall designate a project manager who shall be the principal point of contact for the Wilmington District in administering this contract. The Contractor's project manager shall be responsible for all coordination to ensure the work is accomplished in a professional manner. Any directions given that are viewed by the Contractor as a change to the SOW affecting contract fee or time shall be brought to the immediate attention of the KO or the COR.

COR and technical POCs mail and email information follows:

Stephen J. Fabian, P.G.

Stephen.J.Fabian@usace.army.mil

U.S. Army Corps of Engineers

Wilmington District

Attn: Stephen Fabian

69 Darlington Avenue Wilmington, NC 28403‐1343

Kelley J. Kaltenbach, P.G.

Kelley.J.Kaltenbach@usace.army.mil

U.S. Army Corps of Engineers Wilmington District

Attn: K.J. Kaltenbach

69 Darlington Avenue

Wilmington, NC 28403‐1343

II. STATEMENT OF SERVICES

Description of Work.

The Contractor shall perform a total of 71 vibracores and 434 lab samples for this project. All coordinates are provided in Tables 1 and 2. Following vibracore collection, the Contractor shall carefully transport the vibracores to a facility for processing. The collected vibracores shall be processed and field logs and photos provided to the COR. Following the receipt of the vibracore logs and photos, SAW will require at least 5-business days to determine the lab test sampling interval for soils testing.

All vibracores shall be horizontally referenced to North American Datum (NAD) 1983 North Carolina

State Plane Feet. The top and bottom of each vibracore shall be referenced to the MLLW vertical datum.

Sampling procedures for all vibracores shall be accomplished in accordance with paragraph “Vibracore

Sampling.” Field logs, Preliminary Drilling Logs, and Final Drilling Logs for all vibracores shall be accomplished with the paragraph “Drilling Logs.” In addition to the Field Logs, Preliminary Drilling Logs, and Final Drilling Logs, the Contractor shall take detailed photographs of each vibracore to highlight changes in lithology. Laboratory testing on USACE-designated samples shall be accomplished in accordance with the paragraph “Laboratory Testing Procedures.”

Performance Period.

The Contractor shall mobilize to the site to begin vibracoring within 5-calendar days following SAW acceptance of the Accident Prevention Plan (APP). The entire work, including the vibracore drilling, mailto:Stephen.J.Fabian@usace.army.mil mailto:Kelley.J.Kaltenbach@usace.army.mil logging, photographing, laboratory analyses, and the Final Report (hard copy and electronic files) should be submitted within 180 calendar days from time of award.

USACE Furnished Materials.

Maps showing the vibracore locations are provided in Figures 1 through 6, while the vibracore coordinates are provided in Tables 1 and 2.

An Open Ground database, which includes the Open Ground core log template, shall be used to generate the drilling logs and will be furnished after contract award. GIS files of existing vibracores, NOAA charts, and bathymetric data are available on request.

Designated sampling intervals for laboratory testing shall be provided by the Wilmington District, based on the Contractor’s Field Logs and photos. The sample intervals for each field log will be provided to the contractor within 5-business days upon receipt of the field logs and photographic mosaic logs.

Vibracore Sampling.

The Contractor shall designate vibracores from Hatteras Ferry-Rollinson Channel as “HFCRC-25-V-

###.” Vibracores from Big Foot Slough-Silver Lake Harbor shall be designated as “BFS-25-V-###.”

Vibracores shall be performed within 150-feet (horizontally), yet as close as practicable to, the locations provided by the Wilmington District (Tables 1 and 2).

Vibracore drilling shall be accomplished by vibrating a vertical 3-inch diameter sampling tube to the run length (10- or 20-feet) designated for each vibracore, as shown in Tables 1 and 2. Per the South Atlantic

Regional Biological Opinion (SARBO) for the Endangered Species Act, the vibracore sampler shall not be operated until the vibracore platform contacts the seafloor/channel bottom and vibracore barrel contacts the seafloor/channel bottom. The vibracore sampler shall not be operated during retrieval operations (SARBO, 2020). The recovered sediments in each vibracore should not be less than 75% of penetration/drive length unless the collected vibracore encounters refusal. To document vibracore refusal, penetrometer data collection shall be recorded and presented to verify vibracore refusal.

Vibracore refusal is defined as the sampling barrel having a penetration rate of less than 0.2 feet over a 30-second period. If vibracore refusal is encountered at the seabed, the Contractor shall offset up to 20 feet and conduct an additional vibracore attempt at a separate location within 20 horizontal feet of the original point. Location information and refusal depth shall be recorded for each location where refusal is encountered.

Life safety concerns encompass issues or situations directly jeopardizing physical safety and well-being.

Given the dynamic nature of the project area, which includes factors such as shallow water, tidal influence, shifting shoals, and exposure to swell, if access to a vibracore location becomes impossible due to life safety concerns, immediate communication between the COR, KO, and the contractor's project manager is required to assess the need for location abandonment. The contractor shall initiate communication via phone to the COR and via writing to both the COR and KO, detailing the encountered conditions during the attempt to access the respective vibracore location. Additionally, the contractor shall coordinate between the vibracoring vessel captain, the contractor’s project manager, and the Government to determine the location of an alternate vibracore within the project area. Tube lengths associated with the vibracores in Tables 1 and 2 will not change even if the original locations are moved elsewhere. Conversely, if an alternate location which supports the Government’s project goals is not determined, no alternative vibracore shall be collected and the contractor shall not receive payment for the collection, logging, or photographing of that respective vibracore.

For each drilled vibracore location, real-time kinematic (RTK) Global Positioning System (GPS) surveying techniques shall be utilized to provide accuracies of 0.2 feet vertically and horizontally. The Contractor shall collect the actual coordinates (Easting and Northing) and top of hole (TOH MLLW) elevation of each vibracore at the time of drilling. Field Logs not containing proper coordinates and TOH will not be accepted. These are required in order for the government to determine the number of lab sample picks per core.

Completed vibracores shall be carefully transported for processing, field logging, and visual soils classification. A photographic mosaic log depicting the stratigraphic horizons relative to depth shall be produced for each vibracore. Vibracores shall be field classified and logged in accordance with ASTM

D2488 “Standard Practice for Description and Identification of Soils (Visual-Manual Procedure).” The top and bottom of the vibracores and vibracore photos shall be referenced to MLLW vertical datum.

Once field classification of the vibracore lithology is complete, the field logs, core photographs, and penetrometer records shall be submitted to the Wilmington District to select samples for laboratory testing.

Drilling Logs.

All drilling logs shall be developed using USACE Bentley OpenGround Cloud configured for the project. USACE will provide necessary permissions to Contractors entering data. If the Contractor does not already have a license for OpenGround Cloud, the Contractor must obtain user-specific "named user" or concurrent licenses. Field logs, at a minimum, shall include the date and time when each vibracore was taken, run time for the vibracore, the horizontal location of the vibracore (NAD 1983 North Carolina

State Plane Feet), tide-corrected ocean bottom elevation (MLLW), and a visual description of the stratigraphy and the lithology in accordance with ASTM 2488-09A. Supplemental information including depths for the entire length of recovered material, vibracore recovery, and refusal depth shall also be denoted. The Wilmington District shall determine the sample intervals to be tested. Following

Wilmington District’s sample selections, the Contractor shall designate the samples “S-1, S-2, S-3, etc…”, with top and bottom depths listed and send to the laboratory for testing. Once the lab data are compiled, Preliminary Drilling Logs shall be developed with the necessary information mentioned above and include the laboratory data specified in laboratory testing procedure. Once the Preliminary Drilling Logs are reviewed and comments are addressed, they will be the Final Drilling Logs and can be submitted as part of the Final Report.

The Contractor shall conduct a QA/QC of the Final Drilling Logs to ensure that the coordinates and

TOH elevations are correct, stratigraphic field classifications are consistent and within 1-USCS letter/symbol of the laboratory tested sample, and the graphical symbology utilized reflects the stratum described. The Contractor shall provide a legend or key to soil symbols and terms utilized.

Laboratory Testing Procedures.

Laboratory testing shall be the responsibility of the Contractor. Laboratory tests shall be conducted by a

USACE validated soils testing lab. A listing of USACE validated laboratories is available at:

http://www.erdc.usace.army.mil/Media/Fact-Sheets/Fact-Sheet-Article-View/Article/476661/materials-testing-center/.

For estimating purposes, 71 vibracores are to be collected. The maximum number of samples for which laboratory testing is required shall not exceed 434 samples. The exact number of samples per vibracore will be dependent of the materials encountered. Although up to 434 samples could be tested, the Contractor will only be paid for samples that are selected for laboratory testing by the Wilmington

District. The Wilmington District shall determine the depth intervals for each test sample based on the

Field Logs and photographs. The laboratory test reports shall include the project name, laboratory name, http://www.erdc.usace.army.mil/Media/Fact-Sheets/Fact-Sheet-Article-View/Article/476661/materials-testing-center/ http://www.erdc.usace.army.mil/Media/Fact-Sheets/Fact-Sheet-Article-View/Article/476661/materials-testing-center/ vibracore number, sample identification number, and date each sample was tested. The final laboratory test results shall be included in the Final Report and on the Preliminary and Final Drilling Logs.

Three (3) test procedures shall be performed on each sample:

1) ASTM D6913, “Particle‐Size Distribution (Gradation) of Soils Using Sieve Analysis,” modified by using the following sieve sizes: 1‐in., 3/8‐in., No. 4, No. 7, No. 10, No. 14, No. 18, No. 25, No. 35, No. 40, No. 60, No. 80, No. 120, No. 170, No. 200, and No. 230;

2) ASTM D2487 “Standard Practice for Classification of Soils for Engineering Purposes (Unified

Soils Classification System);” and

3) Visual, volumetric percentage of shell and rock fragment determination. Visual percent shell content and visual percent rock fragment content shall be estimated for the 1-in., 3/8-in., and No.

4 sieve sizes.

Reporting Requirements.

A Draft Report shall be submitted to USACE for review and comment. The Draft Report shall include a description of the work, details of the underlying geology, final vibracore locations on maps and in a table, Preliminary Drilling Logs, penetration rate records and graphs, core photographic mosaics, and lab test data, complete with gradation tables and curves for each sample tested with a summary table.

The Contractor shall revise the Draft Report, incorporating Wilmington District’s comments. The

Contractor shall submit the Final Report to the COR for USACE to review and backcheck that all comments have been appropriately addressed. Once accepted the revised report will become the Final

Report.

Once accepted, the Contractor shall furnish one (1) hard copy of the Final Report, electronic/digital files containing the Final Report, all the lab test data in Excel and PDF formats, the USACE Bentley

OpenGround database file, and ArcGIS shapefiles, layers, or feature classes showing vibracoring locations. Electronic/digital lab test data files shall contain the project name at the top, vibracore number, sample identification number, depth of sample, visual classification, and percentage passing each sieve (highlight #200 sieve), visual percent of rock and shell content, sorting, and the mean and median grain size for each sample.

Cost Proposal.

The Contractor shall submit a detailed cost proposal and a vibracore plan to USACE as part of his or her proposal. The detailed cost proposal shall be based on Table 4.

The Contractor’s cost shall assume vibracore sampling and logging, all laboratory testing procedures, Final Drilling Logs in USACE Bentley OpenGround format, photographic mosaic logs, penetration rate graphs, a USACE Bentley OpenGround database, an Excel summary spreadsheet of all laboratory data, and a Final Report including Final Drilling Logs and laboratory analyses.

In addition, vibracores and select samples will be requested by the Wilmington District for archiving purposes. Assume no more than 7 vibracores and 43 soil samples. For archiving purposes, the vibracores shall be cut into 5-foot segments. The vibracores and select samples shall be shipped and delivered to the Wilmington District at the time the hard copy of the Final Report is provided. The costs for shipping vibracores and select samples shall be included in the contractor’s cost estimate.

Lastly, the Contractor shall provide details on the daily costs for vessel operation and number of days required for the vibracore drilling effort. The vibracore plan shall include a field work schedule with number of vibracores per day, the type of vibracore machine, the size of the vibracore tube, the material from which the tubes are made, the size and description of the vessel(s) to be used, the number of boats and crew members, the qualifications of the laboratory performing analyses, and a description of the survey equipment to be used to collect coordinate and elevation data. The contractor should also account for the field site conditions when developing his/her cost proposal during vibracore collection.

Submittals.

Submittals shall be sent electronically to the KO, COR and Technical POC’s listed below:

• Rosalind.M.Shoemaker@usace.army.mil (or her designee);

• Stephen.J.Fabian@usace.army.mil; and

• Kelley.J.Kaltenbach@usace.army.mil.

The Final Report shall be bound and titled; “Hatteras Ferry-Rollinson Channel and Big Foot Slough

Channel-Silver Lake Harbor, 2025 Subsurface Investigation and Geotechnical Laboratory Testing

Results” containing all the elements and meeting the requirements herein. One hard copy of the Final

Report shall be submitted by the Contractor and deemed acceptable by USACE before final payment is made.

Final Submittals shall be made to the following recipient:

Mr. Stephen Fabian, P.G. (CESAW‐ECP‐EG), Geologist, Geotechnical and Dam Safety Section, 69 Darlington Avenue, Wilmington, NC 28403‐1343.

One hard copy and digital copy of the Final Report shall be mailed to Mr. Fabian.

Safety.

Safety of all parties is a major concern. The Contractor shall coordinate the work effort with the U. S.

Coast Guard and comply with all their requirements and requests. The Contractor shall ensure that drilling operations have a minimal effect on navigation by other mariners. The Contractor shall comply with guidance established in the U.S. Army Corps of Engineers Safety Manual, EM 385-1-1, dated 15

MAR 2024 and any applicable State, Federal, and U. S. Coast Guard regulations. The Contractor shall submit an Accident Prevention Plan to the Wilmington District for review within 7 calendar days following contract award. The Wilmington District will require a minimum of 7 calendar days to review and provide comments. The Contractor shall revise the APP and resubmit to the Wilmington District for review and acceptance. No field work shall be performed until the plan is accepted by the

Wilmington District.

The plan shall follow the guidelines established in EM 385-1-1 to include: the location of the work site;

discussion on what conditions are unfavorable for field work to occur; verified emergency contact information for the local US Coast Guard station(s); evacuation plan to the nearest medical facility;

emergency radio frequencies and telephone numbers; required safety equipment; lockout/tagout requirements and procedures; certified first aid personnel; spill prevention and HAZMAT information;

and an Activity Hazard Analysis. The Contractor shall be responsible for conducting a daily Safety Brief and Risk Assessment prior to commencing work each day. All personnel shall be properly clothed and protected for working on the water. Wilmington District reserves the right to halt vibracoring operations for any safety violation.

mailto:Rosalind.M.Shoemaker@usace.army.mil mailto:Stephen.J.Fabian@usace.army.mil

Anti-Terrorism and Operations Security.

The contractor shall pre-screen candidates using the E-Verify Program (http://www.uscis.gov/e-verify) website to meet the established employment eligibility requirements. The Contractor shall ensure that each Candidate has two valid forms of government issued identification prior to enrollment to ensure the correct information is entered into the E-Verify System. An initial list of verified/eligible candidates shall be provided to the COR no later than 2 business days after the initial contract award. When contracts are with individuals, the individuals shall be required to complete a Form I-9, Employment

Eligibility Verification, with the designated Government representative. This Form shall be provided to the KO and shall become part of the official contract file.

Payment Process

The Contractor may submit invoices to the COR for work that has been completed. The invoice will be reviewed and verified by the KO and COR.

Request for Payment.

The Contractor shall provide a copy of the invoice on completion of agreed services. The invoice shall be provided through the US Postal Service or email, to the Technical Point of Contact or the Contracting

Officer’s Representative (POC/COR). The contractor shall ensure that the following are included on the invoice:

• Contract #

• Invoice #

• Company Name

• Invoiced Line Item(s) must match the Contract Line Item(s)

• Small Business, Veteran Owned, or 8A – If applicable, indicate on invoice http://www.uscis.gov/e-verify

Table 1. Hatteras Ferry-Rollinson Channel, Vibracore name, coordinates, and length of tube.

Vibracore Northing Easting Tube Length (ft)

HFCRC-25-V-001 2981125.8 548299.0 20

HFCRC-25-V-002 2979801.1 548206.8 20

HFCRC-25-V-003 2979398.9 547599.7 10

HFCRC-25-V-004 2979989.9 547194.8 20

HFCRC-25-V-005 2979754.3 546241.5 10

HFCRC-25-V-006 2978896.5 546178.3 20

HFCRC-25-V-007 2979659.6 545424.6 10

HFCRC-25-V-008 2978635.3 544945.0 20

HFCRC-25-V-009 2978178.0 545691.0 20

HFCRC-25-V-010 2977497.6 544666.0 20

HFCRC-25-V-011 2976736.1 545951.5 20

HFCRC-25-V-012 2976769.0 546910.1 20

HFCRC-25-V-013 2976760.1 547882.0 20

HFCRC-25-V-014 2976312.2 548782.7 20

HFCRC-25-V-015 2975739.7 549626.5 20

HFCRC-25-V-016 2975195.9 550432.6 20

HFCRC-25-V-017 2974561.6 551222.2 20

HFCRC-25-V-018 2973819.4 551893.6 20

HFCRC-25-V-019 2973034.7 552485.2 20

HFCRC-25-V-020 2972246.9 553138.0 20

HFCRC-25-V-021 2971485.7 553761.2 20

HFCRC-25-V-022 2961889.8 554296.4 10

HFCRC-25-V-023 2960951.8 554464.5 10

HFCRC-25-V-024 2959867.4 554665.6 20

HFCRC-25-V-025 2958818.6 554688.6 20

HFCRC-25-V-026 2959040.3 554072.3 20

HFCRC-25-V-027 2960122.9 554053.3 20

HFCRC-25-V-028 2959261.8 553497.8 10

HFCRC-25-V-029 2960415.8 553440.5 20

HFCRC-25-V-030 2961596.7 553107.0 10

HFCRC-25-V-031 2960685.5 551993.1 20

HFCRC-25-V-032 2961803.9 551943.3 20

HFCRC-25-V-033 2960686.8 550898.7 20

HFCRC-25-V-034 2961381.2 550651.6 20

HFCRC-25-V-035 2961027.1 549781.1 20

HFCRC-25-V-036 2960666.0 548885.3 20

Table 2. Big Foot Slough Channel-Silver Lake Harbor, Vibracore name, coordinates, and length of tube.

Vibracore Northing Easting Tube Length (ft)

BFS-25-V-001 2892932.3 525525.1 10

BFS-25-V-002 2892443.4 524420.5 10

BFS-25-V-003 2893418.0 524633.9 10

BFS-25-V-004 2892793.1 523770.8 20

BFS-25-V-005 2893838.6 523705.0 20

BFS-25-V-006 2893138.1 522702.8 20

BFS-25-V-007 2894218.0 522966.4 20

BFS-25-V-008 2893711.2 521888.4 20

BFS-25-V-009 2894548.5 522003.4 20

BFS-25-V-010 2894247.3 521056.5 20

BFS-25-V-011 2893949.9 520439.5 20

BFS-25-V-012 2894591.4 520271.4 20

BFS-25-V-013 2894888.9 519026.1 20

BFS-25-V-014 2895516.4 512747.5 20

BFS-25-V-015 2895284.6 514414.2 20

BFS-25-V-016 2894693.9 513638.1 10

BFS-25-V-017 2894214.7 514417.7 20

BFS-25-V-018 2894683.5 515205.0 20

BFS-25-V-019 2893164.5 514317.5 20

BFS-25-V-020 2893663.1 516036.6 20

BFS-25-V-021 2892785.6 516496.1 20

BFS-25-V-022 2891603.7 515235.9 20

BFS-25-V-023 2889965.6 516215.7 10

BFS-25-V-024 2888721.0 517867.2 10

BFS-25-V-025 2887925.9 517082.8 20

BFS-25-V-026 2887245.0 518463.2 20

BFS-25-V-027 2886450.0 517474.5 10

BFS-25-V-028 2886281.6 518841.3 20

BFS-25-V-029 2885034.2 518025.3 10

BFS-25-V-030 2884695.7 519315.5 10

BFS-25-V-031 2883485.0 518378.7 10

BFS-25-V-032 2883446.9 519968.3 10

BFS-25-V-033 2881694.3 518883.7 10

BFS-25-V-034 2881921.4 520370.8 10

BFS-25-V-035 2880365.1 519377.1 10

Table 3. Activity Description and Timeline.

Activity

Duration

(calendar days)

USACE

Responsibility

Contractor

Responsibility

Contract Award 180 X

Accident Prevention Plan (Total Days) 22

APP – Draft and Submit 7 X

USACE Review of Draft APP 7 X

APP Revisions and Resubmittal 7 X

USACE Review of Revised APP and Acceptance 1 X

Field Work and Geotech Analysis (Total Days) 128

Mobilization 8

Vibracore Collection 70 X

Logging and Photographs – Generate and Submit 13 X

Lab Sample Picks 7 X

Laboratory Analysis 30 X

Vibracore Report (Total Days) 30

Draft Report - Generate and Submit 10 X

SAW Review of Draft Report 5 X

Report Revisions and Resubmit 5 X

SAW Review of Final Report and Acceptance 5 X

Final Submittal (Final Report Hard Copy and Electronic Files and Archive Vibracores and Samples) 5 X

Total Calendar Days 180 Calendar Days

If the Contractor encounters unforeseen delays in meeting an event on the timeline, he or she shall notify the KO and COR in writing no earlier than 5-business days prior to the due date. The Contractor shall describe the circumstances that led to the delay, his or her immediate actions to mitigate impacts to schedule, and event/timeline updates.

Table 4. Bidding/Cost Proposal

Item No.

Description Quantity Unit

Unit Cost

Subtotal Cost

0001 Mobilization and Demobilization 1 Job

0002 Vibracore Collection 71 Each

0003 Vibracore Logging and Photographing 71 Each

0004 Lab Testing 434 Each

0005 Report 1 Job

0006 Vibracore Archives 7 Each

0007 Lab Sample Archives 43 Each

Figure 1. Vibracore locations within Hatteras Ferry and Rollinson Channels. This area contains 36 x vibracores, 10- to 20-foot long each. The coordinates are provided in Table 1. The mapped bathymetry represents the conditions at the time of survey and is subject change.

Figure 2. Vibracore locations within in the vicinity of Silver Lake Harbor and Big Foot Slough Channel. This area contains 35 x vibracores, 10- to

20-foot long each. The coordinates are provided in Table 2. The mapped bathymetry represents the conditions at the time of survey and is subject change.

Figure 3. Detailed view of vibracore locations within Hatteras Ferry and Rollinson Channels. The coordinates are provided in Table 1. The mapped bathymetry represents the conditions at the time of survey and is subject change.

Figure 4. Detailed view of vibracore locations within Hatteras Ferry Channel. The coordinates are provided in Table 1. The mapped bathymetry represents the conditions at the time of survey and is subject change.

Figure 5. Detailed view of vibracore locations in the vicinity of Silver Lake Harbor. The coordinates are provided in Table 2. The mapped bathymetry represents the conditions at the time of survey and is subject change.

Figure 6. Detailed view of vibracore locations in Big Foot Slough Channel. The coordinates are provided in Table 2. The mapped bathymetry represents the conditions at the time of survey and is subject change.