35 20 23_Dredging_REVb.pdf

POST 45 CHARLESTON UPPER HARBOR W912HP20B0004

MAINTENANCE AND NEW WORK DREDGING

SECTION 35 20 23 PAGE 1

SECTION 35 20 23

DREDGING_REVb

PART 1 GENERAL

SUMMARY

REFERENCES

DEFINITIONS

Required Dredging Prism Allowable Overdepth Prism Side Slopes Excessive Dredging Acceptance Section Floating Pipeline Submerged Pipeline

MEASUREMENT AND PAYMENT

Continuity of Work Work Covered by Contract Price Estimated Quantities Variations In Estimated Quantity – Dredging Shoaling

SUBMITTALS

CHARACTER OF MATERIALS

Maintenance New Work Historical Geotechnical Reports Unidentified Known Objects Debris

CONSOLIDATED REPORT

PART 2 PRODUCTS

WOOD MATERIALS

PART 3 EXECUTION

ORDER OF WORK

INSPECTION

Inspection Requirements Noncompliance

PLANT

Equipment and Machinery

Capacity of Plant Walkways and Guardrails Signal Lights Communications Automatic Identification System Use of More Than One Dredge k2tsoh9c Text Box Accompanying Amendment 02 (AM#02)

SECTION 35 20 23 PAGE 2

Pipelines Submerged Pipeline Floating Pipeline

3.3.2.2.1. Marking the Location of the Pipeline

Buoys

Lights, Lighted Buoys and Dredging Aids Markers Noncompliance Plant Removal

NAVIGATION AIDS AND DREDGING AIDS

Relocation of Navigation Aids for Dredging Aids to Navigation within the Dredging Areas

MISPLACED MATERIAL

Dredged Material Equipment

PLACEMENT OF EXCAVATED MATERIAL IN UPLAND PLACEMENT AREA

Hydraulic Fill Construction of Yellow House Creek Cross Dike Use and Operation of Placement Area Discharge Points and Discharge lines Use of Spillways

Stoplogs Monitoring of Dikes and Spillways Monitoring Discharges from Spillways Maintenance of Upland Placement Area

Existing Drainage Ditches New Drainage Ditches Maintenance and Repair of Dikes Maintenance and Repair of Spillways

Drainage of Surface Water Completion Inspection of Placement Areas

SURVEY

Quantity Surveys

Survey Specifications Horizontal Positioning of Surveys Vertical Positioning of Surveys Government Equipment Datum and Bench Marks

3.7.1.5.1. Horizontal Datum

3.7.1.5.2. Vertical Datum

Dispute of Surveys Performed by Government

EXAMINATION AND ACCEPTANCE

Examination Acceptance of Work

Bed Leveling – Reporting and Documenting

ACCOMMODATIONS AND MEALS FOR INSPECTORS

Office Subsistence Transportation

SECTION 35 20 23 PAGE 3

PART 1 GENERAL

SUMMARY

The work covered by this section consists of furnishing all plant, equipment, labor and materials, and performing all work required for the removal and placement of all material, layout and accomplishment of all dredging work, and the movement of plant in accordance with these specifications and as indicated on the contract drawings.

REFERENCES

U.S. ARMY CORPS OF ENGINEERS (USACE)

EM 385-1-1 Safety and Health Requirements Manual

EM 1110-2-1003 Hydrographic Surveying Manual

DEFINITIONS

Required Dredging Prism

The dredging prism shall be defined as the area down to the required depth and to the associated side slopes as specified on the contract drawings. The dredging prism does not include the allowable overdepth in the channel or allowable overdepth in the associated side slopes.

Allowable Overdepth Prism

To cover inaccuracies of the dredging process, material actually removed from within the specific areas to be dredged below the required dredging prism to a depth of not more than shown on the contract drawings will be computed and paid for at the contract price. This material is considered to be optional and shall not be considered for purposes of determining any variation in quantity. See Paragraph “Variations In Estimated Quantity – Dredging”.

Side Slopes

Dredging of side slopes is required for acceptance of new work only. Material actually removed from the required side slope section shown on the contract drawings will be computed and paid for at the dredging unit cost per cubic yard for that acceptance section. For the purpose of dredging, the side slopes constitute a design criteria for new work dredging. Side slopes may fall flatter than those shown on the contract drawings. However, no payment will be made for material removed outside these specified limits.

Excessive Dredging

Material taken from beyond the limits as extended in the provisions of Paragraphs "Allowable Overdepth Prism" and "Side Slopes" above will be considered as excessive dredging for which payment will not be made. Nothing herein shall be construed to prevent payment for the removal of shoals performed in accordance with Subsection EXAMINATION AND ACCEPTANCE or Paragraph “Shoaling” and as applicable and as further set forth under Subsection MEASUREMENT AND PAYMENT.

Acceptance Section

SECTION 35 20 23 PAGE 4

For the purpose of acceptance, each acceptance section is shown on the contract drawings. Acceptance sections may be modified as described in Paragraph “Acceptance of Work”.

Floating Pipeline

Floating pipeline is any pipeline which is suspended at or above the water surface.

Submerged Pipeline

Submerged pipeline is any pipeline which is resting on the river, channel, or ocean bottom and shall be anchored on the channel bottom.

MEASUREMENT AND PAYMENT

The Contractor shall dredge each acceptance section to the required depths as indicated on the contract drawings. The required dredging prism for each Contract Line Item shall be considered for purposes of determining any variation in quantity. See Paragraph “Variations In Estimated Quantity – Dredging”.

The required amount of material removed and placed by dredging according to contract specifications will be measured and paid for by the cubic yard in situ based on before and after dredge surveys performed by the Government.

The volume computation method used will be determined according to the most accurate method for each acceptance section and the type of survey performed and may include: the TIN to Channel Single TIN method for before dredge (BD) volumes and the TIN to Channel Dual TIN method for after dredge (AD) volumes, the Philadelphia Pre-dredge Side Slope Non-contour method for BD volumes and the Philadelphia Post-dredge Side Slope Non-contour method for AD volumes, or the Cross Sections and Volumes Philadelphia Predredge method for BD volumes and the Cross Sections and Volumes Philadelphia Postdredge method for AD volumes. After dredge volumes will be calculated from a survey made within five (5) days (weather permitting) after dredging in the Acceptance Section that has been completed. This includes the area within the limits of the allowable overdepth and side slopes described in Paragraph “Allowable Overdepth Prism” and Paragraph “Side Slopes”, less any deductions that may be otherwise required by these specifications. Payment will be made using the after dredge method based on the before dredge survey and after dredge survey for each acceptance section. The net required and net overdepth volumes will be used for payment.

All volume calculations will be computed using HYPACK software. Calculations will be made using survey data collected in accordance with subparagraph “Survey Specifications”. Multi-beam data will be binned to a 3-foot by 3-foot matrix using the average soundings within each cell. Data used for volume computations will be available to the Contractor upon request.

Payment items for the work of this contract will be made as listed in the Bidding Schedule and described below. All costs for items of work, which are not specifically mentioned or are incidental to completion of the work, are to be listed in a particular lump sum or unit price payment item that is most closely associated with the work involved. The lump sum price and payment made for each item listed shall constitute full compensation for furnishing all plant, labor, materials, and equipment, and performing any associated Contractor quality control, environmental protection, meeting safety requirements, testing and reports, and for performing all work required for

SECTION 35 20 23 PAGE 5

which separate payment is not otherwise provided.

Progress payments shall be made monthly in accordance with the contract clause PAYMENTS UNDER FIXED-PRICE CONSTRUCTION CONTRACTS. Progress payments shall be based on a mutually agreeable percentage of completed work, as described in Paragraph “Work Covered By Contract Price.”

Monthly progress payments will be based on approximate quantities estimated and agreed on with the construction representative using information taken from the surveys as described in Subsection SURVEY.

Within the limit of available funds, the Contractor will be required to excavate the entire quantity of material necessary to complete the work specified herein, be it more or less than the amounts above estimated, and as modified by Subsection EXAMINATION AND ACCEPTANCE and Paragraph “Shoaling”.

All work shall be done in accordance with the contract at the contract price or prices, except as may be affected by Paragraph “Variations In Estimated Quantity – Dredging”.

Final acceptance of the whole or a part of the work and deductions or corrections of deductions made thereon will not be reopened after having once been made, except on evidence of collusion, fraud or obvious error, and the acceptance of a completed section shall not change the time of payment of the retained percentages of the whole or any part of the work.

Continuity of Work

Final payment for and formal acceptance of Acceptance Sections will not be rendered until the Acceptance Section is excavated to the full depth and extents required by the contract. If the Contractor requests, and the Government approves, to adjust the extents of an Acceptance Section, in accordance with Paragraph “Acceptance of Work,” and then is unable to complete that Acceptance Section prior to the planned departure of plant, then the Contractor shall be responsible for the removal of any additional material that may shoal, accrete, or otherwise be deposited in that Section prior to acceptance by the Government, at no additional costs to the Government. See provisions in Subparagraph “Shoaling.” Progress Payments will be made in accordance with SECTION 35 20 23, Subsection MEASUREMENT AND

PAYMENT.

Work Covered by Contract Price

ITEM 0001, MOBILIZATION AND DEMOBILIZATION - MAINTENANCE AND NEW WORK

DREDGING IN CHARLESTON UPPER HARBOR, shall include all costs connected with the mobilization and demobilization of all dredging plant and equipment required to complete the work to and from the project site. Sixty percent (60%) of this CLIN will be paid when scheduled mobilization work has been completed, and the remaining forty percent (40%) will be paid when scheduled demobilization has been completed. If incremental or multiple mobilizations and demobilizations are anticipated, then the line item price shall be spread proportionately across the various mobilization or demobilization events as detailed in the accepted project schedule. The percentage assigned to each event will be paid after completion of the event. The sum of all the mobilizations shall not exceed sixty percent (60%) of CLIN 0001, and the sum of all the demobilizations shall not exceed forty percent (40%) of CLIN 0001, and the total payment shall not exceed the CLIN 0001 price. All effort associated with moving the plant and equipment within the project site shall be included in the unit price for the Line Item Number being worked and not in the mobilization and demobilization CLIN 0001.

SECTION 35 20 23 PAGE 6

ITEM 0002, DREDGING OF UNCLASSIFIED MAINTENANCE MATERIAL IN CHARLESTON UPPER

HARBOR ACCEPTANCE SECTIONS 1-8, shall include the cost of removal and placement of all material and the layout and accomplishment of all work, as specified herein or indicated on the contract drawings. The movement of plant between acceptance sections, as indicated on the contract drawings, shall be included in the unit price. All MAINTENANCE materials shall be paid at the contract price under CLIN 0002. Payment for MAINTENANCE material removed shall not exceed the Before Dredge quantities for each acceptance section.

The contract price per cubic yard for dredging shall be applicable to quantities in any extensions of the dredging limits except as provided in Paragraph “Variations In Estimated Quantity – Dredging”. Calculated volumes for cubic yardage will be determined according to Subsection SURVEY for payment purposes. Materials dredged under CLIN 0002 shall not be used for construction of cross dike at Yellow House Creek Placement Area.

ITEM 0003, DREDGING OF UNCLASSIFIED NEW WORK MATERIAL IN CHARLESTON UPPER

HARBOR ACCEPTANCE SECTIONS 1-8, shall include the cost of removal and placement of all material and the layout and accomplishment of all work, as specified herein or indicated on the contract drawings, including any additional costs for the construction of the cross dike at Yellow House Creek Placement Area using NEW WORK materials. The movement of plant between acceptance sections, as indicated on the contract drawings, shall be included in the unit price. All NEW WORK materials shall be paid at the contract price under CLIN 0003. Payment for NEW WORK material removed shall not exceed the Before Dredge quantities for each acceptance section. The contract price per cubic yard for dredging shall be applicable to quantities in any extensions of the dredging limits except as provided in Paragraph “Variations In Estimated Quantity – Dredging”. Calculated volumes for cubic yardage will be determined according to Subsection SURVEY for payment purposes.

OPTIONAL ITEM 0005, REMOVAL OF UNIDENTIFIED KNOWN OBJECTS, shall include all costs connected with removal and disposal of the objects noted on the contract drawings as described in paragraph “Unidentified Known Objects” below.

OPTIONAL ITEM 0006, MOBILIZATION AND DEMOBILIZATION PIER X-RAY SOUTH, shall include all costs connected with the mobilization and demobilization of all the Contractor's dredging plant and equipment. This item shall also include all costs related to security badging and access requirements and related coordination with JBC and NPTU personnel.

OPTIONAL ITEM 0007, DREDGING WORK PIER X-RAY SOUTH, shall include the cost of removal and placement of all material and the layout and accomplishment of all work, as specified herein or indicated on the contract drawings. The contract price per cubic yard for dredging shall be applicable to quantities in any extensions of the dredging limits except as provided in Paragraph “Variations In Estimated Quantity – Dredging”. Calculated volumes for cubic yardage will be determined according to Subsection SURVEY for payment purposes.

OPTIONAL ITEM 0008, MOBILIZATION AND DEMOBILIZATION MARADS PIERS S,T,U, shall include all costs connected with the mobilization and demobilization of all the Contractor's dredging plant and equipment. This item shall also include all costs related to security badging and access requirements and related coordination with JBC and NPTU personnel.

OPTIONAL ITEM 0009, DREDGING WORK MARADS PIERS S,T,U, shall include the cost of removal and placement of all material and the layout and accomplishment of all work, as specified herein or indicated on the contract drawings. The k2tsoh9c Text Box

(AM#01)

k2tsoh9c Text Box

(AM#02)

k2tsoh9c

(/AM#02)

SECTION 35 20 23 PAGE 7

contract price per cubic yard for dredging shall be applicable to quantities in any extensions of the dredging limits except as provided in Paragraph “Variations In Estimated Quantity – Dredging”. Calculated volumes for cubic yardage will be determined according to Subsection SURVEY for payment purposes.

OPTIONAL ITEM 0010AA, MOBILIZATION AND DEMOBILIZATION (TC DOCK), shall include all costs connected with the mobilization and demobilization of all the Contractor's dredging plant and equipment.

OPTIONAL ITEM 0010AB, DREDGING WORK (TC DOCK - DESC), shall include the cost of removal and placement of all material and the layout and accomplishment of all work, as specified herein or indicated on the contract drawings.

OPTIONAL ITEM 0010AC, DREDGING WORK (TC DOCK - MSDDC), shall include the cost of removal and placement of all material and the layout and accomplishment of all work, as specified herein or indicated on the contract drawings. The contract price per cubic yard for dredging shall be applicable to quantities in any extensions of the dredging limits except as provided in Paragraph “Variations In Estimated Quantity – Dredging”. Calculated volumes for cubic yardage will be determined according to Subsection SURVEY for payment purposes. Contractor shall also comply with any special conditions contained the permit to dredge TC Dock found in the ATTACHMENT Naval Weapons Station Dredging Permit.

Estimated Quantities

The total estimated quantity of material necessary to be removed from within the specified limits to complete the work are as follows:

REQUIRED

MAINTENANCE

DREDGING

PRISM

REQUIRED

NEW WORK

DREDGING

PRISM

ALLOWABLE

OVERDEPTH

PRISM

TOTAL ACCEPTANCE

SECTION

NO. LOCATION CY MEAS. * CY

MEAS.*

CY

MEAS.** CY MEAS.

1 Daniel Island Bend 95,000 48,000 28,000 171,000

1597+51 to 1625+66

2 Clouter Creek Reach 73,000 457,000 167,000 697,000

1625+66 to 1695+66

3 Navy Yard Reach 40,000 222,000 135,000 397,000

1675+66 to 1749+49 1695+66 to 1749+49

4 North Charleston Reach 39,000 353,000 129,000 521,000

1749+49 to 1800+75

5 Filbin Creek Reach 20,000 323,000 113,000 456,000

1800+75 to 1853+00 k2tsoh9c

(/AM#01)

k2tsoh9c

(AM#01)

SECTION 35 20 23 PAGE 8

6 Port Terminal Reach 25,000 53,000 43,000 121,000

1853+00 to 1873+26

7 Ordnance Reach 160,000 185,000 81,000 426,000

1873+26 to 1905+63

8 Ordnance Reach Turning Basin 450,000 841,000 95,000 1,386,000

1873+26 to 1905+63

Pier X-Ray South 5,000 N/A 4,000 9,000

Pier S 45,000 N/A 7,000 52,000

Pier T 40,000 N/A 6,000 46,000

Pier U 35,000 N/A 5,000 40,000

TC Dock DESC 1,000 N/A 1,000 2,000

1703+90 to 1704+90

MSDDC 34,000 N/A 14,000 48,000

1704+90 to 1720+83

TOTALS 907,000 2,482,000 795,000 4,184,000

1,062,000 2,482,000 828,000 4,372,000

NOTE:

* 1. Required depth will be as shown on the contract drawings. The required dredging prism quantities include the required maintenance, new work and side slope material associated with the required depth. Side slopes are required to be cleared for new work acceptance only.

** 2. The allowable overdepth quantities include the allowable overdepth in the side slopes as shown on the contract drawings.

Variations In Estimated Quantity – Dredging

In reference to contract Clause FAR 52.211-18 VARIATIONS IN ESTIMATED QUANTITY, consideration for equitable adjustment will be determined as follows:

Where the quantity of a pay item in this contract is an estimated quantity and where the actual quantity of material within the required dredging prism varies more than fifteen percent (15%) above or below the stated estimated quantity within the dredging prism, an equitable adjustment in the contract unit price will be made upon demand of either party. The equitable adjustment will be based upon any increase or decrease in costs due solely to the variations above one hundred fifteen percent (115%) or below eighty-five percent (85%) of the estimated quantity within the dredging prism. No k2tsoh9c

(/AM#01)

SECTION 35 20 23 PAGE 9

consideration for an adjustment in the contract unit price will be given for any variation in quantities of material below the required dredging prism or outside the associated side slope lines; such quantities will not be subject to any adjusted unit price.

Shoaling

If before the contract is completed, shoaling occurs in any section previously accepted, including shoaling in the finished channel because of the natural lowering of the side slopes, dredging at contract price, within the limits of available funds, may be done if agreeable to both the Contractor and the Contracting Officer. Shoaling, including natural lowering of the side slopes, that occurs after the before dredge survey for an Acceptance Section and before final acceptance of that Section, shall be the responsibility of the Contractor to remove, at no additional costs to the Government, except in the case of the Government directing the Contractor to move at the direction of the Contracting Officer.

SUBMITTALS

Government approval is required for submittals with a "G" designation;

submittals not having a "G" designation are for information only. When used, a designation following the "G" designation identifies the office that will review the submittal for the Government. Submit the following in accordance with this section.

SD-01 Preconstruction Submittals

Plant & Equipment Schedule (Reference Paragraph “Equipment and Machinery”)

SD-05 Design Data

Work Plan (Reference Subsection ORDER OF WORK)

SD-07 Certificates

Stoplog Certification (Reference Subsection WOOD MATERIALS)

SD-11 Closeout Submittals

Consolidated Report (Reference Subsection CONSOLIDATED REPORT); G

CHARACTER OF MATERIALS

All dredge excavation will be unclassified, regardless of the nature of the materials encountered. It is the responsibility of the bidders to analyze the associated geotechnical information located in the ATTACHMENTS to determine for themselves the character and dredgeability of the materials, the volumes of different types of materials, and the difficulties inherent to performing the scoped work. The Contractor is responsible for properly preparing himself and his equipment to deal with the existing geologic conditions at the project site.

Maintenance

Materials to be excavated are principally those which naturally accumulated as a result of shoaling that has occurred since the areas were last dredged.

SECTION 35 20 23 PAGE 10

The previously maintained depths were 47 feet MLLW in the channel plus up to 2 feet allowable overdepth, plus any advanced maintenance in applicable areas. For purposes of this contract, all materials in Acceptance Sections 1- 6 shoaler than 48 feet MLLW shall be defined as maintenance, and shall be paid at the contract price for maintenance dredging in those templates where maintenance material is included. In areas of this project where advanced maintenance has been previously authorized and dredged, the maintenance depths will be 50 feet MLLW (Acceptance Sections 7 and 8). These areas are identified on the contract drawings by cross hatching.

Soils encountered during maintenance dredging are typically unconsolidated and unlithified in-shoal material consisting of very soft to soft organic silts, variable-sized sand, clay, silt, gravel, and admixtures of these soil types.

New Work

For the purpose of this contract, all materials in Acceptance Sections 1-6 dredged below 48 feet MLLW within the construction template shall be defined as new work. In areas of this project where advanced maintenance has been previously authorized and dredged, the new work depths will be any materials below 50 feet MLLW (Acceptance Sections 7 and 8). All materials dredged in wideners shall be considered new work.

Geotechnical information concerning the geologic materials to be dredged in the new work is provided in the ATTACHMENTS. Elevations shown on the boring logs and condition survey reflect the condition of the channel bottom at the time the survey/boring was taken. Elevation correction for MLW on borings is MLLW = MLW -0.20 feet. The Contractor should be aware that a portion of the geologic material that was originally sampled by a particular boring may have been removed by subsequent dredging or erosion. Plan Sheets C-02 through C-09 show the locations of all geotechnical borings drilled within the harbor acceptance sections. A summary boring table, which contains boring coordinates, elevation intercept with respect to 2011 bathymetric surveys, and general soils information is provided in the ATTACHMENTS. Drilling logs from borings drilled prior to 2004 may show coordinates that are in World Geographic Reference System or South Carolina State Plane, North American Datum 1927, Survey Feet. These coordinate locations were converted by USACE to South Carolina State Plane International Feet, North American Datum 1983, and are shown on the plan sheets and in the boring summary information table in the ATTACHMENTS.

New Work Material that is expected to be encountered within Acceptance Sections 1 and 2 generally consists of very stiff calcareous lean silt and clay, with lesser occurrences of dense to very dense silty to clayey sand.

Standard Penetrometer Test (ASTM D1586) maximum N-values range from 18 to

100. New work material in Acceptance Section 3 is similar in composition, consisting of very stiff calcareous fat clay, hard calcareous silty lean clay, and loose to medium dense calcareous clayey sand. Maximum SPT N-values range from 0 to 25. New work material in Acceptance Section 4 consists of stiff to very stiff calcareous lean inorganic silt, stiff to very stiff calcareous lean clay, and medium dense calcareous clayey sand. Maximum SPT N-values range from 9 to 28. New work material in Acceptance Sections 5 through 8 are similar to the aforementioned acceptance sections. New work material to be encountered consists of stiff to very stiff deposits of calcareous fat clay, stiff to very stiff calcareous lean silty clay, highly-indurated claystone, and medium dense calcareous and non-calcareous clayey sand.

Maximum SPT N-values range from 9 to 43.

SECTION 35 20 23 PAGE 11

Historical Geotechnical Reports

The Contractor may download and reference Appendix B “Geotechnical” from the Final Feasibility Report and Environmental Impact Statement, available through the USACE, Charleston District website:

http://www.sac.usace.army.mil/Portals/43/docs/civilworks/post45/finalreport/3 _Appendix%20B%20-%20Geotechnical.pdf?ver=2015-07-02-134531-903.

The table below lists the subsurface investigation reports that have been commissioned by USACE or the SCSPA, pertaining to the harbor areas to be dredged in this contract. These reports are geotechnical and/or environmental in scope and they span a time period from 1986 to 2013. The reports are available for download with the solicitation.

Investigation Type # Pages 1986 OSI Subsurface Investigation Charleston Harbor Vibracore Drilling 467 p.

2012 CCU Hard Bottom & Cultural Resource Survey Geophysical

Survey 293 p. & data

2012-2013 Anamar Environmental Testing Upper & Lower Harbor

Vibracore Drilling 113 p + appendices

Unidentified Known Objects

Several objects are known to be in the dredge prism and are explicitly denoted on the contract drawings. Objects may be in the channel or in the side slopes above the dredge template. The known objects have not been positively identified. Known information is summarized in the table below.

Information in the table below is the government’s best interpretations of multibeam survey data from May 2020, and magnetometer survey data from 30 June 2020, and is not guaranteed to be fully accurate or complete. Images corresponding to the Object ID Name can be found in Attachment H. All such known objects shall be removed from the dredged area shall be removed from the water. Disposal shall be the responsibility of the Contractor and disposal shall be outside the limits of government property. Disposal of objects will not be permitted on the riverbanks, in navigable waterways, or Government provided dredged material placement areas unless otherwise specified. All objects not explicitly denoted on the contract drawings and the following table shall be considered under the paragraph “Debris” below.

Object

Object

ID

Name Easting Northing

Least Depth

(ft)

Object Length

(ft)

Object Width

(ft)

Detection Method

1 T14 2323254.10 373817.00 48.00 85 5 Multibeam 2 T71 2322828.20 374385.20 13.81 310 5 Multibeam 3 M1a** 2320170.20 376003.40 N/A N/A N/A Magnetometer 3 T53 2320031.00 376006.70 47.80 70 1 Multibeam 3 M1b** 2319875.20 376015.00 N/A N/A N/A Magnetometer 4 T60 2318965.00 376489.30 45.60 20 3 Multibeam 5 T63 2318760.70 376942.70 48.39 35 5 Multibeam 6 T65 2317810.80 378862.30 42.68 20 3 Multibeam 7 T46 2320537.40 390944.90 48.29 38 5 Multibeam 8 T66 2321202.50 390889.70 23.10 20 5 Multibeam

9, 10 T67* 2322053.70 390969.40 19.00 15 3 Multibeam 11 M2a** 2321110.90 375156.70 N/A N/A N/A Magnetometer http://www.sac.usace.army.mil/Portals/43/docs/civilworks/post45/finalreport/3_Appendix%20B%20-%20Geotechnical.pdf?ver=2015-07-02-134531-903 http://www.sac.usace.army.mil/Portals/43/docs/civilworks/post45/finalreport/3_Appendix%20B%20-%20Geotechnical.pdf?ver=2015-07-02-134531-903

SECTION 35 20 23 PAGE 12

11 M2b** 2321015.00 375045.80 N/A N/A N/A Magnetometer 12 M3a** 2320465.40 375829.10 N/A N/A N/A Magnetometer 12 M3b** 2320415.90 375741.10 N/A N/A N/A Magnetometer 13 M4*** 2321037.30 374510.00 N/A N/A N/A Magnetometer

*Two objects in this location.

** Magnetometer points indicate beginning and end of object that may be buried.

***No indication of object from multibeam indicates object may be buried.

Debris

Bidders should expect to encounter some debris during dredging operations such as, but not limited to, logs, trees, wood debris, misplaced riprap, misplaced stone, chains, buoy anchors, cables, miscellaneous trash, pipes, ropes, and other natural or artificial obstructions. The Government has no knowledge of existing wrecks, wreckage, or other material of such size or character as to require the use of explosives or special or additional plant for its economical removal aside from those identified on the contract drawings and described in paragraph “Unidentified Known Objects”. If in the judgment of the Contracting Officer the debris can be removed during normal dredging operations, it shall be removed by the Contractor. Debris removed from the dredged area shall be removed from the water. Disposal shall be the responsibility of the Contractor and disposal shall be outside the limits of government property. The removal and disposal of this debris shall be accomplished at no additional cost to the Government. Disposal of debris will not be permitted on the riverbanks, in navigable waterways, or Government provided dredged material placement areas unless otherwise specified.

CONSOLIDATED REPORT

The Contractor shall submit a consolidated report within 30 days after completion of all work associated with this contract and shall include, as a minimum, the information listed on the form, CONSOLIDATED REPORT provided in the ATTACHMENTS. Final payment to the Contractor will not be made until this report has been received by the Contracting Officer.

PART 2 PRODUCTS

WOOD MATERIALS

Lumber and timber piles shall be fabricated before preservative treatment.

Each piece of treated lumber or timber shall be branded, by the producer, in accordance with AWPA M6. All wood will be in contact with salt water or salt water splash and therefore shall be treated in accordance with AWPA UC5B (Marine Use Central Waters) with water-borne preservative. The Contractor shall be responsible for the quality of treated wood products.

Stoplogs shall be 3 inch x 6 inch (3”x6”) tongue and groove lumber, Southern Yellow Pine #2 or approved equal. Style of tongue and groove shall be submitted to the Contracting Officer for acceptance. Stoplog certification is required and shall be submitted to the Contracting Officer for confirmation or compliance to the specifications listed.

PART 3 EXECUTION

ORDER OF WORK

There is no order of work under this contract. Placement of material at k2tsoh9c Text Box

(/AM#01)

k2tsoh9c

(AM#01)

SECTION 35 20 23 PAGE 13

Yellow House Creek Placement Area shall not begin until the maintenance dredging project of Joint Base Charleston Channel is complete under a separate contract and with the approval of the Contracting Officer, in order to maintain the requirement that only one dredge pipe discharges into the cell at a time. The Joint Base Charleston Channel dredging contract is anticipated to be complete no later than January 2021. All materials pumped after placement of the cross dike shall be placed into the newly created cell to the north east.

Upon Yellow House Creek Placement Area becoming available, Contractor should complete for full acceptance the Acceptance Section he is currently working in, then promptly move to Ordnance Reach Turning Basin to begin maintenance dredging work. If more than one dredge is being used, then work may occur concurrently so long as Ordnance Reach Turning Basin maintenance dredging is begun as soon as practicable once Yellow House Creek Placement is available.

If awarded, CLIN 0006 Pier X-Ray South must be dredged while there is no ship at the pier. It is anticipated that the pier will be vacant from 1 May 2021 to 1 12 July 2021.

The Contracting Officer may alter order of work, and if necessary, may direct the Contractor to move at no additional cost to the Government. Dredging of acceptance sections shall be listed in a work plan for performing the work to be submitted by the Contractor. The plan shall include a schedule, equipment list and description, and description of how the work is to be accomplished.

The work plan shall be submitted for Contracting Officer’s acceptance a minimum of 14 days before any construction is to be performed.

Approval of the Contracting Officer must be received by the Contractor before dredging may commence on the next acceptance section prior to the completion and acceptance of the previous acceptance section.

INSPECTION

All work will be conducted under the general direction of the Contracting Officer and shall be subject to full-time inspection by his appointed Representative to ensure strict compliance with the terms of the contract.

Inspection Requirements

The presence of a Quality Assurance Representative shall not relieve the Contractor of responsibility for the proper execution of the work in accordance with the specifications.

The Contractor shall:

(a) Furnish, on the request of the Contracting Officer or any Quality Assurance Representative, the use of such boats, boatmen, laborers, and material forming a part of the ordinary and usual equipment and crew of the dredging plant as may be reasonably necessary in inspecting the work. However, the Contractor will not be required to furnish such facilities for the surveys prescribed in the Subsection EXAMINATION AND ACCEPTANCE.

(b) Furnish, on the request of the Contracting Officer or any Quality Assurance Representative, suitable transportation from all points on shore designated by the Contracting Officer to and from the various pieces of plant, and to and from the placement area.

Noncompliance k2tsoh9c Text Box

(AM#02)

k2tsoh9c Text Box

(/AM#02)

k2tsoh9c Text Box

(AM#01)

k2tsoh9c

(/AM#01)

SECTION 35 20 23 PAGE 14

Should the Contractor refuse, neglect, or delay compliance with these requirements, the specific facilities may be furnished and maintained by the Contracting Officer and the cost thereof will be deducted from any amounts due or to become due the Contractor.

PLANT

The Contractor agrees to keep on the job sufficient plant to meet the requirements of the work. The plant shall be in satisfactory operating condition and capable of safely and efficiently performing the work as set forth in these specifications. Inspection of equipment listed in Paragraph "Equipment and Machinery" shall be made prior to commencement of work in order to determine if it is satisfactory so as to meet the requirements of work. The plant shall be subject to inspection by the Contracting Officer and the U.S. Coast Guard at all times. The plant list is the minimum which the Contractor agrees to place and maintain on the job unless otherwise determined by the Contracting Officer, and its listing thereon is not to be construed as an agreement on the part of the Government that it is adequate for the performance of the work.

Equipment and Machinery

A complete listing of all dredging plant and machinery to be used in the work, including booster pumps, barges, skiffs, and other related equipment, shall be submitted with the Plant and Equipment Schedule prior to beginning work. The plant list, as specified in Section 00 45 00 REPRESENTATIONS & CERTIFICATIONS, shall include manufacturer and year of manufacture, operational capacities, safety features, operating and licensing requirements for operators, and a description of where and how the item of equipment or plant is to be employed in the work.

Capacity of Plant

No reduction in the capacity of the plant employed on the work shall be made except by written permission of the Contracting Officer. The measure of the "capacity of the plant" shall be its actual performance on the work to which these specifications apply.

Walkways and Guardrails

All floating plant and pipelines used as access ways or working platforms shall be equipped with walkways and guardrails conforming to Corps of Engineers Manual EM 385-1-1 and meet OSHA requirements for worker safety.

Signal Lights

The Contractor shall display signal lights and conduct his operations in accordance with the General Regulations of the Department of the Army and of the Coast Guard governing lights and day signals to be displayed by towing vessels with tows on which no signals can be displayed, vessels working on wrecks, dredges, and vessels engaged in laying cables or pipe or in submarine or bank protection operations, lights to be displayed on dredge pipe lines, and day signals to be displayed by vessels of more than 65 feet in length moored or anchored in a fairway or channel, and the passing by of other vessels of floating plant working in navigable channels, as set forth in Commandant U.S. Coast Guard Instruction M16672.2, Navigation Rules:

International-Inland (COMDTINST M16672.2), or 33 CFR 81 Appendix A (International) and 33 CFR 84 through 33 CFR 89 (Inland) as applicable.

SECTION 35 20 23 PAGE 15

Communications

The Contractor will be required to furnish, maintain, and operate one FM narrow-band radio transmitter-receiver with a capacity of not less than (1) watt, equipped for operating on maritime channels 13 and/or 16 at 156.65 MHz.

This frequency shall be used for communications with passing vessels, harbor pilots, and bridge operators and has been approved by the Federal Communications Commission for this purpose. It is not required that this frequency be disabled after termination of the contract. Contractor will be required to maintain a Contractor owned cellular phone for communication with Corps of Engineers personnel.

Automatic Identification System

The Contractor is required to have the Automatic Identification System (AIS).

The Contractor shall have AIS transponders on all floating plants at all times when working in Charleston Harbor. The AIS provides a means for ships to electronically exchange ship data including: identification, position, course, and speed with other nearby ships and VTS stations. AIS is intended to assist the vessel's watch standing officers and allow maritime authorities to track and monitor vessel movements.

Use of More Than One Dredge

No more than one dredge working under this contract shall discharge into each placement area at any given time.

Pipelines

The Contractor will be responsible to ensure that all pipelines are properly maintained during this contract. All pipelines for hydraulic machines must be kept in good condition at all times and any leaks or breaks along their length must be promptly and properly repaired. Dredge pipelines that are floating, to include rubber discharge hoses, or supported shall display lights at night and in periods of restricted visibility in accordance with U.S. coast Guard regulations and 33 CFR 88.15.

Submerged Pipeline

Submerged pipeline shall rest on the channel bottom. Where a submerged pipeline crosses a navigation channel, the top of the pipeline and any anchor securing the pipe shall be no higher than the authorized channel depth in which the pipe is placed. Pipelines shall not be permitted to fluctuate between the water surface and the channel bottom or lie partially submerged.

Routine inspections of the submerged pipe shall be conducted to ensure anchorage.

Floating Pipeline

The dredge operator will assure that the pipeline remains fully submerged and on the bottom; however, when it is necessary to raise the pipeline, proper clearances shall be made and maintained and the entire length of the pipeline will be adequately marked.

3.3.2.2.1. Marking the Location of the Pipeline

Pipeline shall be marked in accordance with local USCG requirements and approved by the Government Designated Authority (GDA).

SECTION 35 20 23 PAGE 16

(a) Unless otherwise specified by the USCG, submerged pipelines are considered to require special marks and shall have a USCG approved flashing yellow light.

(b) Indicators, such as signs or buoys that state “DANGER SUBMERGED PIPELINE” will be placed at the beginning and end of the pipeline. In addition, indicators are required beginning in areas which reduce the charted depth by more than 10 percent and, as a minimum, every 1000 feet. (304.8 m) to clearly warn of the pipeline length and course.

(c) If barges or other vessels are used to anchor the beginning and/or end of the submerged pipeline, they shall be lighted in accordance with 33 CFR 88.13.

(d) Within a navigation channel, each end of the pipeline shall be identified with a regulatory marker buoy.

(e) Lengths of submerged pipeline located outside of the navigation channel, which reduce the charted depth by more than 10 percent, will be identified with high visibility buoys marked with 360 degree visibility retro-reflective tape, such as orange neoprene buoys, placed at an interval not to exceed 500 feet. (152.4 m) to clearly show the pipeline length and course.

(f) All submerged pipeline or fittings with less than six (6) feet of clearance between the top of the pipeline and mean low water will be marked with the same type of light meeting the requirements of this subsection and spaced approximately one hundred (100) feet apart.

Buoys

All marker buoys shall be painted yellow and display the same yellow flashing light as required for floating or supported dredge pipelines meeting the requirements of this subsection.

(1) Buoys used to anchor booster pumps

(2) Buoys used to anchor or mark stored equipment i.e. (barges, pipeline etc.)

(3) Buoys used to mark or anchor dredge pipelines and this includes floating and submerged pipeline leading to placement areas.

(4) Any other buoys the U.S. Coast Guard or Contracting Officer requires to insure a safe harbor free from hazards to navigation must be marked and display yellow flashing lights meeting the requirements stated in this subsection.

(5) In-water lines (rope, chain, and cable, including the lines to secure turbidity curtains) must be stiff, taut, and unable to loop or tangle to minimize the possibility of a sea turtle becoming entangled. Examples of such lines are heavy metal chains or heavy cables that do not readily loop and tangle. For flexible in-water lines, such as nylon rope or any lines that could loop or tangle, care must be taken to ensure that all lines are rigged properly, utilizing the correct amount of line to best prevent the line from looping and tangling. In all instances, no excess line is allowed in the water.

Lights, Lighted Buoys and Dredging Aids Markers

All lights, lighted buoys and dredging aids markers must be maintained, operable and on station at all times to insure a safe harbor. The placement, markings and lighting shall meet all US Coast Guard Regulations, EM 385-1-1 and the Special Requirements found in this specification.

SECTION 35 20 23 PAGE 17

Cutterhead

For OPTIONAL Dredging of Pier X-Ray South, if awarded, the cutterhead shall not be engaged/turned on when not embedded in the sediment, to the maximum extent possible.

Noncompliance

The Contracting Officer will notify the Contractor in writing of any noncompliance with the foregoing provisions. Such notice, when delivered to the Contractor or his authorized representative at the site of the work, shall be deemed sufficient for the purpose. Within 24 hours after receipt of such notice, the Contractor shall mail, or personally deliver to the Contracting Officer, a complete proposal of the prompt correction of the noncompliance. The Contracting Officer will review the proposal and return it to the Contractor approved, subject to such changes or conditions as he finds necessary to assure correction of noncompliance. Immediately upon receipt of such approval, the Contractor shall begin the corrective work and shall carry it to completion. If the Contractor fails or refuses to submit his proposal or to proceed with the corrective work, the Contracting Officer may suspend all or any part of the work until satisfactory corrective action has been taken. No part of the time lost due to any such suspension shall be made the subject of a claim for extension of time nor for excess costs or damages by the Contractor. If he so elects, the Contracting Officer may cause the corrective work to be accomplished by others, in which event the cost thereof shall be chargeable against moneys otherwise due the Contractor from the Government.

Plant Removal

Upon completion of the work, the Contractor shall promptly remove all plant, including all pipelines, pipeline anchors, ranges, buoys, piles, and other markers or obstructions.

NAVIGATION AIDS AND DREDGING AIDS

Relocation of Navigation Aids for Dredging

The USCG requires notification sixty (60) days in advance to remove or relocate any navigation aids to facilitate dredging operations. Due to time constraints the Government will notify the USCG in advance of an estimated time and location that dredging operations will be accomplished. However, after award and prior to commencement of dredging it is the responsibility of the Contractor to coordinate with the USCG for the actual removal or relocation of any navigation aids within or near the areas to be dredged. The Contractor will also notify the Contracting Officer in advance of the time and location of the aids that will require relocation. The Contractor shall coordinate the removal or relocation of navigation aids with the following:

Commander, 7th Coast Guard District (OAN) Brickell Plaza Federal Bldg., Room 406 909 S.E. 1st Avenue Miami, Florida 33131-3050 ATTN: Chief of Planning and Marine Information Phone: (305) 350-5621

Commander, Sector Charleston

SECTION 35 20 23 PAGE 18

US Coast Guard 196 Tradd Street Charleston, South Carolina 29401 ATTN: Aids to Navigation Officer Phone: (843) 740-3180 Fax: (843) 740-3189 Email: secchasn-wm@uscg.mil

Aids to Navigation within the Dredging Areas

The Contractor shall be responsible for any damage to aids to navigation within the dredging areas or areas adjacent thereto caused by his operations.

MISPLACED MATERIAL

Any material that is deposited or allowed to flow elsewhere than in places designated or approved by the Contracting Officer will be considered as misplaced material and will not be paid for.

Dredged Material

Should the Contractor deposit any material outside the designated placement areas approved by the Contracting Officer, the Contractor shall give immediate notification of the location of the misplaced material and when required, mark or buoy this location. If in the opinion of the Contracting Officer this misplaced material will in any way be a hazard to navigation and requires removal, the Contractor shall be required to remove the misplaced material immediately and deposit said material in an area designated by the Contracting Officer at no additional cost to the Government.

Equipment

Should the Contractor, during the progress of the work, lose, dump, throw overboard, sink, or misplace any material, plant, machinery, or appliance, which in the opinion of the Contracting Officer may be dangerous to or obstruct navigation, the Contractor shall recover and remove the same within the timeframe directed by the Contracting Officer. The Contractor shall give immediate notice, with description and location of such obstructions, to the Contracting Officer or Quality Assurance Representative, and when required shall mark or buoy such obstructions, until the same are removed. Should he refuse, neglect, or delay compliance with the above requirements, such obstructions may be removed by the Contracting Officer, and the cost of such removal may be deducted from any money due or to become due the Contractor, or may be recovered under his bond. The liability of the Contractor for the removal of a vessel wrecked or sunk without fault or negligence shall be limited to that provided in Sections 15,19, and 20 of the River and Harbor Act of March 3, 1899 (33 U.S. C. 410 et seq.).

PLACEMENT OF EXCAVATED MATERIAL IN UPLAND PLACEMENT AREA

Material dredged under this contract shall be transported to and placed in the Clouter Creek Placement Area (Highway Cell) and the Yellow House Creek Placement Area as shown on the contract drawings and in accordance with these specifications. In the event of dike breaching, the pumping of material into the placement area shall be immediately stopped until repairs are implemented. Contractor shall only actively discharge dredged material from one pipe per cell at any time.

SECTION 35 20 23 PAGE 19

Hydraulic Fill Construction of Yellow House Creek Cross Dike

A cross dike shall be built across Yellow House Creek Placement Area in accordance with the drawings and specifications. Only new work materials consisting of stiff calcareous silts and clays, known as Cooper Marl, shall be used to create the cross dike template as shown on the contract drawings.

Requirements are for minimum dimensions. The intention is for the new work material to create a base for a future cross dike that will be compacted and shaped under a future contract. It is anticipated that there will be significant displacement as material is placed. Other new work sediments and maintenance materials not used for cross dike construction shall be placed away from the cross dike so as to not cause erosion or washing over of the new cross dike or existing dikes. All materials pumped after placement of the cross dike shall be placed into the newly created cell to the north east.

Use and Operation of Placement Area

The Contractor shall assume all responsibility for use and operation of the placement areas such that they contain all the material to be dredged under…