R-7246 Addendum 4 spec.pdf

R-7246 Addendum 4

August 22, 2025

ADDENDUM NO. 4

PLANS AND SPECIFICATIONS NO. R-7246

ALAMITOS BAY ENTRANCE CHANNEL DREDGING

IN THE CITY OF LONG BEACH, CALIFORNIA

NOTICE TO HOLDERS OF PLANS AND SPECIFICATIONS

Please note the following changes, clarifications, and additions:

1. SPECIFICATIONS

Changes to specifications for the ALAMITOS BAY ENTRANCE CHANNEL DREDGING (Specification Number R-7246):

Division J Technical Specifications Section 01 71 13 Mobilization and Demobilization and Section 35 20 23 Dredging and Sediment are replaced in their entirety with the attached documents

All modifications are incorporated into this addendum, and a summary of the revisions and descriptions of changes is provided below:

DIVISION J TECHNICAL SPECIFICATIONS:

The following changes to Division J Technical Specifications were made to conform with Addendum 3 changes to Division C Bid to the City of Long Beach (Bid Form), which combined Bid Line Items for dredging and beach nourishment (Base Bid Line Item No. 5 and 6 and Bid Additive Line Item No. 7 and 8).

SECTION 01 71 13 MOBILIZATION AND DEMOBILIZATION:

- Paragraphs 4.01-A and 4.02-A have been edited for clarity.

- Paragraphs 4.01-B and 4.02-B have been deleted.

SECTION 35 20 23 DREDGING AND SEDIMENT PLACEMENT:

- Paragraphs 1.02-A.4 and 1.02-A.5 have been edited to match the Addendum 3 Bid

Form Line Item changes.

- Paragraph 1.02-A.16 has been added to define Allowances.

- Paragraph 1.06-B.4 replaces additive with allowance

- Paragraph 3.04-C has been edited to match the Addendum 3 Bid Form Line Item changes.

- Paragraphs 3.10-B and 3.10-C have been edited for clarity following Addendum 3

RFI response 27 regarding owner acceptance of dredging subsections.

- Paragraphs 4.01-A, 4.01-B, and 4.01-C have been edited to match the Addendum

3 Bid Form Line Item changes.

Department of Public Works 411 West Ocean Boulevard, 5th Floor Long Beach, CA 90802

(562) 570-6383

R-7246

Department of Public Works 411 West Ocean Boulevard, 5th Floor Long Beach, CA 90802

(562) 570-6383

- Paragraphs 4.01-D, 4.01-E, 4.01-F have been deleted.

- Paragraphs 4.02-A, 4.02-B, and 4.02-E have been edited to match the Addendum

3 Bid Form Line Item changes.

- Paragraphs 4.02-C and 4.02-D have been deleted.

CONTACT: Before the Bid opening, prospective Bidders shall direct any communications regarding this Work to:

City of Long Beach, Department of Public Works Project Management Bureau 5th Floor, City Hall 411 W. Ocean Boulevard Long Beach, CA 90802 Attention: Michael Lau / TidelandsCIP E-mail: Michael.Lau@psomas.com / TidelandsCIP@longbeach.gov

Communications may be written or oral, but the City is not bound by any oral interpretation of the Contract Documents made by any City employee, nor does the City guarantee the accurate transcription of oral questions.

PREPARED BY: Michael Lau

ACKNOWLEDGED BY:

Company Name

Print Name Title

Signature Date

ALAMITOS BAY ENTRANCE CHANNEL

DREDGING (Specification Number R-7246)

Division J Technical Specifications

SECTION 01 71 13 MOBILIZATION AND

DEMOBILIZATION

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MAINTENANCE DREDGING AND June August 2025

BEACH NOURISHMENT PROJECT ADDENDUM 4 R-7246

SECTION 01 71 13

MOBILIZATION AND DEMOBILIZATION

PART 1 – GENERAL

1.01 SUMMARY

A. This Section consists of the work of Mobilization and Demobilization for the project as noted in the following items below.

1. Work for Mobilization as specified in this Section consists of pre-construction expenses and activities for preparatory work and operations performed at the start of the Contract work including preparation of the Contractor Work Plan.

2. Work for Demobilization as specified in this Section includes completion of project record documents and operations performed at the end of the Contract work.

3. Mobilization and Demobilization includes facilities such as staging or laydown areas. Site access and staging shall be performed in accordance with the Drawings, Contract Documents, and Section 01 11 00, Summary of Work.

B. Work Not Included:

1. Items which are not to be included in the items of Mobilization and Demobilization are:

a) Any portion of the work covered by a specific Bid Item or incidental work which is to be included in a Bid Item or Items, other than Mobilization and Demobilization.

b) Occasional and repeated moves of personnel and equipment to the Site, such as vendors and material suppliers.

c) Profit, interest on bond money, overhead or management costs which is considered incidental to the work.

1.02 DEFINITIONS AND CLARIFICATIONS

A. Mobilization includes, but is not limited to, operations necessary for movement of personnel, equipment, supplies and incidentals to the Site; for establishment of all temporary offices, buildings and other facilities necessary for Work on project; all bonds; and for all other work and operations which must be performed or are incidental to beginning work including preparing all pre-construction submittals for review and acceptance by the City. The cost for mobilization shall not

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exceed 60 percent of the maximum amount shown in the Bid Schedule for Mobilization/Demobilization.

B. Demobilization includes, but is not limited to, completion and approval of project record documents and operations and maintenance data, operations necessary for removal of personnel, equipment, supplies, property of the Contractor’s employees and all subcontractors, suppliers, and their employees, and incidentals from the Site, Contractor-owned structures, facilities, materials and debris; and for all other work and operations which must be performed or are incidental to completion of work of various contract items, specifically including the satisfactory completion of Project Record Documents.

1.03 DELIVERY

A. Delivery to the Site of construction tools, equipment, materials and supplies shall be accomplished in conformance with local governing regulations.

1.04 PRECONSTRUCTION INSPECTION

A. Prior to starting work, the Contractor shall inspect and photograph the Site with the Owner to show all existing conditions on and adjacent to the Site. Any differences from the Contract Documents shall be recorded prior to commencement of the Work. Submit copies of photos and documentation to identify differing conditions.

PART 2 – PRODUCTS (NOT USED)

PART 3 – EXECUTION

3.01 EXECUTION AND REMOVAL

A. Mobilization: Contractor shall furnish at the Work Site the required personnel, products, construction materials, equipment, tools, and supplies at scheduled time for installation or utilization.

B. Demobilization: The Contractor shall remove trailer, construction tools, apparatus, equipment, unused materials and supplies, and personnel from the Work Site.

PART 4 – MEASUREMENT AND PAYMENT

4.01 MEASUREMENT

A. Measurement of Mobilization and Demobilization will be on a lump sum basis.

The lump sum price offered in the Bid Form must include the following (Bid Item 1):

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1. Preparatory work and operations performed by the Contractor, including, but not limited to, those necessary for the movement and staging of personnel, equipment, supplies, and incidentals to the Work Site.

2. Premiums on bonds and insurance for the Project and for other work and operations that must be performed or costs that must be incurred before the Work at the Work Site.

3. Removal of equipment, remaining materials, and construction-related debris from the Work Site, including the need for multiple mobilizations and demobilizations, if desired.

4. Cleaning and restoring all work areas, storage, and staging locations to their pre-construction condition or better.

B. Measurement of Bid Additive Item 9: Mobilization and Demobilization of Debris Removal Equipment will be on a lump sum basis. The lump sum price offered in the Bid Form must include the following as it relates to debris removal:

1. Preparatory work and operations performed by the Contractor, including, but not limited to, those necessary for the movement and staging of personnel, equipment, supplies, and incidentals to the Work Site.

2. Premiums on bonds and insurance for the Project and for other work and operations that must be performed or costs that must be incurred before the Work at the Work Site.

3. Removal of equipment, remaining materials, and construction-related debris from the Work Site, including the need for multiple mobilizations and demobilizations, if desired.

4. Cleaning and restoring all work areas, storage, and staging locations to their pre-construction condition or better.

4.02 PAYMENT

A. Payment for Mobilization and Demobilization will be made at the Contract lump sum price listed in the Bid for Bid Item 1 Mobilization/demobilization and as authorized, but not to exceed a maximum of 10% of the combination of other Bid Items in the Base Bid (excluding mobilization and demobilization). Incremental payment must be made based on monthly invoices as received.

B. Payment for Bid Additive Item 9: Mobilization and Demobilization of Debris Removal Equipment will be made at the Contract lump sum price listed in the Bid and as authorized, but not to exceed a maximum of 10% of the combination of Bid Additive Items No. 10 and 11 for Debris Removal, Handling, and Disposal.

Incremental payment must be made based on monthly invoices as received.

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END OF SECTION

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ALAMITOS BAY ENTRANCE CHANNEL

DREDGING (Specification Number R-7246)

Division J Technical Specifications

SECTION 35 20 23 DREDGING AND

SEDIMENT PLACEMENT

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SECTION 35 20 23

DREDGING AND SEDIMENT PLACEMENT

PART 1 – GENERAL

1.01 SCOPE

A. The extent and location of the “Dredging and Sediment Placement” work is indicated on the Drawings. The work consists of maintenance dredging Alamitos Bay Entrance Channel to accomplish the required removal of sediments and placing the dredged material within the Beach Nourishment Area to achieve the required grades and elevations within the limits as shown on the Drawings and in accordance with the project permits (including the Mitigation Monitoring and Reporting Program) and as specified. This work includes furnishing all labor, materials, tools, equipment and incidentals required for dredging, sediment transport, sediment placement, and grading per elevation requirements as described in the Contract Documents.

B. The bid quantity and estimated removal volume to achieve the required dredge surface is based on the July 12, 2023, bathymetric survey conducted by eTrac Inc., as depicted on the drawings.

1.02 DEFINITIONS

A. The following definitions shall apply to these technical specifications.

1. Dredging. The removal, transport, and beach placement of materials from below the water surface, as specified in this Section and as indicated in the Contract Documents. Dredging operations shall be conducted from the water using marine-based equipment. All material shall be removed to the required limits and elevations shown on the drawings.

2. Dredging Limits. The horizontal extents by which active dredging operations shall be conducted under this Contract. The Dredging Limits are shown on the drawings. No dredging shall be conducted outside of the Dredging Limits unless approved or directed by the Owner in writing.

3. Required Dredge Elevation. The elevation within an area above which the Contractor is required to remove all material, including associated slough materials, as defined in Article “Dredging Limits.” No elevation tolerance is provided above the Required Dredge Elevation.

4. Payable Overdepth. A surface located 1 foot below the Required Dredge Elevation within the Dredging Limits. The Payable Overdepth Line does apply to Side Slopes. Material removed between the Required Dredge Elevation and the Payable Overdepth is included in the Pay Volume.

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Material removed from below the Payable Overdepth is not payable unless awarded in Bid Additive Item 7 “Additive unit of payable maintenance dredging, transport, and discharge at Beach Nourishment Area, and grading and earthwork at Beach Nourishment Area above the Base Bid Item 5 volume UP TO 128,000 cy for material between -18 feet MLLW plus 1 foot of payable overdredge and Bid Additive Paid Elevation -21 feet MLLW”. The Payable Overdepth does not apply to any areas where the pre-dredge surface elevation is already below the Required Dredge Elevation, where no dredging is necessary or permitted.

5. Bid Additive Paid Elevation. If Bid Additive Item 7 “Additive unit of payable maintenance dredging, transport, and discharge at Beach Nourishment Area, and grading and earthwork at Beach Nourishment Area above the Base Bid Item 5 volume UP TO 128,000 cy for material between -18 feet MLLW plus 1 foot of payable overdredge and Bid Additive Paid Elevation -21 feet MLLW” is awarded, a contiguous surface located 3 feet below the Required Dredge Elevation (i.e. 2 feet below the Payable Overdepth) within the Dredging Limits. In Bid Additive Item 7, the Owner will specify a payable volume for removal ranging between 0 to 128,000 cubic yards located between the Payable Overdepth and the Bid Additive Paid Elevation located within a contiguous area within the Dredging Limits, but that may not include the full Dredging Limits.

Material removed below the Bid Additive Paid Elevation is not payable.

6. Allowable (Non-Payable) Overdepth. A surface located 4 feet below the Required Dredge Elevation (i.e., 3 feet below the Payable Overdepth) that will be allowed for the Contractor to accomplish the means and methods for dredging. Material removed below the Payable Overdepth is not payable. Any dredging below the Allowable Overdepth is considered Excessive Dredging and is not payable.

7. Excessive Dredging. Material removed outside of the Dredging Limits and/or below the Allowable Overdepth is Excessive Dredging. The Contractor shall not perform Excessive Dredging. The Contractor shall not be paid for Excessive Dredging and shall be responsible for any regulatory agency fees, fines, or remedial actions incurred as a result of Excessive Dredging. The Contractor shall not perform Excessive Dredging below the toe of cuts along the exterior limits of dredging to obtain required grades and Side Slopes. The Owner may require the Contractor to correct instances of Excessive Dredging if they believe that existing slopes, structures, or measures of project success are jeopardized in any way by the Excessive Dredging.

8. Hard Material. Any material requiring dredging that cannot be cut and removed using standard dredging equipment and which instead requires

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blasting, boring, or other specialized methods and tools for cutting and removal.

9. Side Slope. The inclined surface left after dredging, between the bottom of the dredge cut at design depth (toe) and the top of cut at the original sediment level. The side slope for this project is to be the natural angle of repose of the existing sediments. Contractor will not be responsible for creating side slopes outside the dredge limits.

10. Slough Material. Material that sloughs into the dredge prism from a side slope or vertical face adjacent to a dredge cut after making a vertical cut to grade or to an adjacent dredge surface. The Contractor shall remove such sediment until the Required Dredge Elevation is met. The estimated volume of Slough Material was calculated assuming a 2H:1V slope from the toe of the Required Dredge Elevation cut and is included in the total dredge quantity presented in the bid form. The Contractor will not be paid for sloughing beyond the indicated design dredge limits.

11. Beach Nourishment Area. The designated area allowed for dredged material placement on Peninsula Beach, per the drawings.

12. Debris. Any man-made, natural solid waste, or non-sediment material removed during dredging operations that is not suitable for placement at the Beach Nourishment Placement Area. Debris encountered may include but is not limited to rock, riprap, armor stone, timber pile stubs, or other non-sediment materials. Rock removed from the existing riprap adjacent to the toe of rock jetty alignment will also be considered Debris.

13. Shoaling. Sediment that accumulates via natural processes or as a result of activities by the Contractor and/or vessel movements.

14. Pay Volume. The calculated quantity of in situ dredged material that will be paid to the Contractor and includes sediments removed from the Dredging Limits above the Payable Overdepth. Pay Volume will be measured in situ using pre- and post-construction surveys.

15. Independent Survey Firm. A firm subcontracted directly to the Contractor that specializes and is licensed in hydrographic and/or topographic surveying (depending on work area) and that has equipment and work force separate from the Contractor’s.

16. Allowances. The allocation of funds for items in the bid schedule for the purpose of identification and budgeting of work where quantities and/or costs are unknown at the time of bidding. If the allowance is either greater or less than the allowance, the contract price shall be increased or decreased accordingly upon proof of the amount expended by the Contractor. Allowances shall include all of the costs of materials, fixtures, michael.lau Pen c

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or equipment and all costs of delivery, handling, and installations.

Contractor shall make no claim for additional compensation because of any increase, decrease or elimination of any allowance item.

1.03 REFERENCE STANDARDS

A. The publications listed below form a part of this Section to the extent referenced.

References shall be the latest edition available as of the date of the invitation to bid unless otherwise specified.

1. 33 Code of Federal Regulations (CFR) 81: 72 COLREGS (International Regulations for Preventing Collision at Sea – 1972): Implementing Rules

2. 33 CFR 84: Annex I: Positioning and Technical Details of Lights and Shapes

3. 33 CFR 85: Annex II: Additional Signal for Fishing Vessels in Close Proximity

4. 33 CFR 86: Annex III: Technical Details of Sound Signal Appliances

5. 33 CFR 89: Inland Navigation Rules: Implementing Rules

6. U.S. Coast Guard (USCG) M16672.2D (2014): Navigation Rules Instruction Manual

7. USACE EM 1110-2-1003 (January 2002) USACE Hydrographic Surveying Engineering Manual; available from:

http://publications.usace.army.mil/publications/eng-manuals/EM_1110-2- 1003_pfl/toc.htm

8. USACE EM 385-1-1 Safety & Health Requirements Manual

1.04 QUALITY CONTROL

A. The Contractor shall perform the work in accordance with the accepted QC Plan as specified in Section 01 40 00, Contractor Work Plan, Section 1.04.C.8 and by using persons qualified to achieve the required and specified level of quality.

B. The Contractor shall establish, provide and maintain a Quality Control (QC) Plan detailing the methods and procedures that will be taken to ensure that all materials and completed construction elements conform to the Drawings, Specifications, and other requirements. No separate payment will be made for QC.

C. The Contractor shall comply with specified standards as minimum quality for the work except where more stringent tolerances, codes, or specified requirements indicate higher standards or more precise workmanship. Examples of potentially

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applicable standards are presented in Article “Reference Standards.” The Contractor shall familiarize itself with pertinent codes and standards.

1.05 SUBMITTALS

A. Pre-Construction Submittals. The Contractor shall submit the following items after Notice of Award.

1. Contractor Work Plan in accordance with Section 01 40 00, Contractor Work Plan.

2. Notice of Commencement of Work: The Contractor shall submit a Notice of Commencement of Work to USACE, as required in the USACE permit.

B. Submittals Required During Construction. The Contractor shall submit the following items during the work, as indicated.

1. Daily Reports. The Contractor shall prepare a Daily Report and Leverman’s Shift Log for each calendar day of dredging and/or sediment placement activity. The Contractor shall submit all forms to be used to the Owner for approval prior to use as part of the Dredge Operations Plan (DOP). All forms shall be filled out completely, including signatures. The Contractor shall submit all original forms to the Owner by noon on the day following the date shown in the forms. Daily Reports will be filled out for every calendar day and for every dredge on site for each day of dredging and/or sediment placement.

If the Contractor fails to submit the report daily, the Owner may withhold payments for undocumented work until such time as the Contractor submits the required information. The Contractor shall make available any records as requested by the Owner to verify that the reports are accurate.

At a minimum, the Daily Report will include a record of:

a) Date and period of working activity

b) Weather conditions

c) Tidal elevations and corresponding times

d) List of equipment and personnel used on the Site that day. Dredge sensor position and movement data (electronic).

e) Materials and equipment received in the 24-hour period

f) Description of the work performed in the 24-hour period

g) The horizontal dimensions of the area dredged that day

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h) The dredge elevations achieved within the areas dredged that day

i) The horizontal dimensions and placement elevations of placed material at the Beach Nourishment Area

j) For days in which a Progress Survey was performed, provide clear graphic depiction of that day’s Progress Survey, with the option to also provide the results in electronic format if requested by the Owner. This applies to both the dredging footprint and Beach Nourishment Area.

k) An estimate of the payable and total volume dredged each day and the cumulative payable and total volume dredged to date

l) An estimate of the payable and total volume placed each day and the cumulative payable and total volume placed to date

m) Effective and non-effective working time

n) Problems encountered. A list of any issues encountered or ongoing that Contractor believes may have cost and/or schedule impacts

o) Full descriptions of any incidents or notable occurrences and corrective actions taken

p) Total number and location (in coordinates) of each sediment placement event or scow load and/or amount of material pumped hydraulically (as applicable). Include the tonnage of each barge and Tonnage Report Logs (as applicable)

q) Description of significant Debris encountered and methods employed to dispose or recycle the Debris

r) QC work performed

s) Description of work being performed within the next 48 hours that includes a list of specific items requiring testing, inspection, monitoring, agency notification, or witnessing by the Owner.

t) Health and safety incidents, near misses, or considerations for upcoming work.

u) Any changes in environmental conditions, including hydrogen sulfide meter readings if collected.

2. Project Construction Schedule Updates. The Project Construction Schedule will be reviewed and updated at each Weekly Construction Progress Meeting. All changes to the Project Construction Schedule of

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more than 3 working days must be documented on the updated Project Construction Schedule and must be submitted both in writing and emailed to the Owner. The Project Construction Schedule must be submitted weekly in hard copy and electronic formats.

The Project Construction Schedule must be used as the basis for justification of time extension requests made by the Contractor. For additional days requested, the Project Construction Schedule must be detailed enough to identify the work item(s) affected and the relationship to changed or added work.

Should any activity not be completed by the stated scheduled date, the Owner will have the right to require the Contractor to expedite completion of the activity by whatever means appropriate and necessary, without additional compensation to the Contractor.

C. Post-Construction Submittals. The Contractor shall submit the following items after completion of construction activities, as described below.

1. Dredging Closure Report. Within 15 working days after the Owner approves the completion of the dredging, the Contractor shall submit a Dredging Closure Report to the Owner, including the following items:

a) Contractor estimate of payable versus total dredge volumes.

b) Contractor estimate of excessive overdredge volumes.

c) Contractor estimate of payable versus total Beach Nourishment volumes.

d) Contractor estimates of incidental debris volume and tonnage disposed of at the Owner’s approved landfill facility and copies of certified weight tickets for debris disposal or recycling.

e) Graphical depiction of areas dredged (can be post-construction survey with addition of final dredged area boundaries or Project Record Drawings).

f) Graphical depiction of areas of the Beach Nourishment Area used for sediment placement (can be post-construction survey with addition of final placement area boundaries or Project Record Drawings).

g) Documentation of any substantive change to the project requirements

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h) One page report listing the Beach Nourishment information to include but not limited to the start and end positions of the beachfill, length and width of the beachfill, start and end dates of beachfill construction, significant events or problems encountered during the beachfill (i.e., any storms that eroded the beach).

2. Notice of Completion of Work: The Contractor shall submit a Notice of Completion of Work to USACE, as required in the USACE permit.

1.06 JOB CONDITIONS

A. Subsurface Conditions and Character of Materials Encountered

1. Sediment sampling of the dredging areas was conducted in late November 2023 into early December 2023 to determine disposal or placement options for dredged sediments; the results are included in the Sampling and Analysis Report (SAR) in Division F. Based on the sediment sampling, the sediment was approved for placement at the Beach Nourishment Area on Peninsula Beach.

2. These samples indicate that the sediment to be dredged is anticipated to be primarily sandy in nature, being classified as silty sand (SM) or poorly graded sand with silt (SP-SM), with composite weighted averages ranging from 15.9% to 30.1% fines. Some silty layers were encountered during the investigation, with individual cores reaching up to 48.0% fines.

3. The Contractor shall review all pertinent information provided in the SAR, and any other pertinent documents regarding material types, and shall satisfy itself regarding the nature of materials present at the Site prior to bidding. The type of materials encountered at the Site may vary from the conditions indicated herein. Variations in the type of materials encountered may occur that do not differ materially from those indicated in the Contract Documents, and if encountered, will not be considered as basis for claims due to differing site conditions.

4. Hazardous materials or wastes are not anticipated to be encountered during dredging, aside from the potential for chemically treated wood waste (CTWW) as described below in this Article. If for any reason the Contractor has reason to believe that hazardous material has been, is being, or is about to be encountered, the Contractor shall immediately notify the Owner and immediately segregate, or be prepared to segregate, the material in question, if encountered. If its presence is confirmed, a method for removal, transportation, and disposal will be determined by the Owner and Contractor, along with an equitable cost adjustment.

5. Hard Material, as may require blasting, boring, or other specialized methods and tools for cutting and removal, is not anticipated to be

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encountered while performing the required dredging. If any Hard Material is encountered, or appears to be incipient, such that a change in equipment type may be necessary, the Contractor shall immediately notify and obtain concurrence from the Owner before proceeding.

B. Anticipated Debris

1. Aside from rock from the riprap adjacent to the toe of the entrance channel jetty walls and possible CTWW discussed in this Section, other significant Debris are not anticipated to exist within the dredge area. However, there is a possibility that other incidences of Debris may be encountered, which may include such items as timber, wood, logs, old pile stubs, tires, cables, chains, ropes, netting, lashing poles, hoses, concrete rock, riprap, asphalt, slag, welding wires, metal, trash, and/or other miscellaneous construction materials.

2. Any Debris encountered and removed during the work shall be removed by the Contractor and properly disposed of at a Contractor-selected and Owner-approved off-site upland commercial landfill location in accordance with federal, state, and local laws and regulations.

3. Should Debris be encountered that cannot be removed with reasonable means and methods, the Contractor shall remove all overlaying material that, in the judgment of the Owner, can be removed using reasonable means and methods.

4. The cost for removing and disposing of Debris (including riprap) shall be included as part of the additive allowance bid item price separate from dredging.

C. Existing Structures. The Contractor shall prevent displacement or damage to existing structures, vessels, and appurtenances at the Site and adjacent properties.

The Contractor shall be responsible for any damage to existing structures, new improvements, and vessels and shall satisfy all claims arising from its operations and from any damage to these structures at no additional cost to the Owner.

D. Utilities. The Owner is not aware of any underground or overhead utilities located within the dredge areas. The Contractor shall conduct its own due diligence to determine whether any utilities could affect dredging operations. If any utilities are encountered during dredging, the Contractor shall immediately terminate work and notify the Owner. The Contractor shall repair, to the pre-construction condition, at its own expense, any damage caused to buried or supported utilities or pipelines by staging, dredging or placement operations.

E. Eelgrass. Eelgrass beds were identified by Marine Taxonomic Services in March, 2024 in the locations depicted on the Drawings. Contractor shall avoid disturbing

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eelgrass areas. No dredging, anchoring, or spudding is allowed within eelgrass areas.

F. Ongoing Activities by the Owner and Recreational Vessels

1. The Contractor shall accommodate and avoid any delays to vessel traffic while conducting dredging operations in the waterway (which may include, but is not limited to, relocating equipment, pipeline, and anchors).

Vessel activity include, but is not limited to, vessel and barge movement within the Site, fueling of vessels, and berthing of unscheduled vessels.

2. The Contractor shall temporarily stop, move, adjust, and/or slow down to avoid delays greater than one hour for recreational vessel movement.

Dredging and sediment transport operations shall be conducted in a manner that avoids interference with other site activities. If the Contractor's construction equipment (e.g., dredge, tug, barges, workboats, anchors, lines, and environmental controls) obstructs the navigable waterway or berthing area so as to hinder movement of commercial vessels, the Contractor’s equipment shall immediately be relocated. All submerged equipment, including but not limited to anchors, anchor lines, pipeline, and environmental controls must be clearly marked above water for other vessel traffic.

3. The Contractor’s accommodation of ongoing vessel activities will be considered incidental to this Contract and will not be considered as a basis for additional time or payment. The Contractor shall make allowances in the Construction Schedule for accommodating vessel movements and berthing activities in the waterway.

4. The Contractor shall coordinate with the Owner and ongoing sand backpassing operations at Peninsula Beach, allowing for backpassing operations to continue when the Owner deems the beach width insufficient to protect residences from storm damage.

5. Any damage to the Contractor’s equipment due to the Contractor’s failure to move operations when required shall be at the Contractor’s sole risk and expense.

G. Working Hours. The Contractor’s standard allowable working hours are 9 hours per day (7:00 a.m. to 4:00 p.m.), 5 days per week (Monday through Friday).

Working outside normal working hours, during night-time hours and weekends, shall be submitted in writing to the Owner and approved by the Owner prior to doing so. No holiday work will be permitted, unless approved in advance by the Owner.

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PART 2 – PRODUCTS (NOT USED)

PART 3 – EXECUTION

3.01 QUALITY OF MATERIALS AND EQUIPMENT

A. Dredging Equipment

1. Dredging operations shall be conducted either through hydraulic or mechanical dredging equipment and operations, or, if desired, a combination of both. The Contractor may propose alternative dredging techniques or equipment, subject to review and approval by the Owner.

However, sediment placement into the Beach Nourishment Area must be conducted by hydraulic dredge equipment only.

2. The dredge and its associated floating platform shall be operated to maintain a draft suitable to work within the shallow waters and avoid running aground.

3. The floating platform, material barges, floating and/or submerged pipelines, and associated equipment shall be maintained to meet the requirements of the work, including the prompt repair of equipment failures.

4. If the Contractor proposes to use electric-powered equipment, the Contractor shall make all arrangements and pay all costs associated with installation, electricity used, and decommission of electrical service for dredging operations. The Contractor shall include this cost in their bid price for general mobilization.

5. If the Contractor proposes to use diesel-powered equipment, the Contractor shall observe all applicable standards and regulations regarding air quality emissions and fueling of the dredging equipment. Equipment must possess or obtain a permit and meet the regulatory requirements of the South Coast Air Quality Management District.

6. The Contractor may elect to use either spuds or anchors to control the position of its equipment, however the Contractor shall obtain Owner approval to use anchors or similar equipment as opposed to spuds due to the higher risk of vessel damage associated with anchors or similar equipment. Anchors, chains, lines, cables, and similar equipment have the potential to interfere or cause harm to passing vessel traffic. If using anchors and/or chains, cables, or similar equipment for vessel positioning, the Contractor shall mark the locations of all anchors and anchoring chains or cables with marker buoys that are clearly visible to passing commercial and residential traffic and meet USCG requirements. The marker buoys will be continuously lit at night.

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7. The dredging equipment shall not be removed from the Site prior to completion and acceptance of the work without prior written permission from the Owner.

B. Dredge Positioning Equipment

1. The dredge will be equipped with real-time differential GPS tied into a real-time kinematic (RTK) positioning system, and the necessary sensors, to enable accurate positioning of the dredge bucket or cutterhead or suction intake of the dredge. The positioning equipment accuracy shall be plus or minus 0.1 foot vertical and plus or minus 1 foot horizontal, to provide dredge equipment accuracy of plus or minus 3 inches vertical and plus or minus 3 feet horizontal. The dredge positioning software shall be capable of the following:

a) Inputting a dredge prism tile (an x, y, z file on a gridded interval of 1 foot by 1 foot)

b) Recording all dredge sensor information electronically to allow the position and movements of the dredge to be reviewed at a later date (playback capability); these playback data are to be provided as part of the Daily Report

c) Producing plots showing the location of each dredge bucket in the dredge area

d) Using a true 3-D computational system to calculate the position of the bucket, accounting for the tilt and list of the dredge platform as well as the standard positioning sensors; IHC Systems’ Excavator Position Monitor (XPM) System and Hypack, Inc.’s Dredgepack System are examples of such a dredge positioning system

e) Displaying to the operator (in real time the position either in cross section or in plan view) where the dredge is working and the position of the dredge head or bucket relative to the required dredge elevations.

2. The error budget of the dredge positioning system shall allow it to work within the stated overdepth tolerances and shall correctly account for all errors associated with measuring the positioning of the bucket, hydraulic cutterhead or suction intake.

3. The Contractor-selected positioning system shall be reviewed and accepted by the Owner.

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4. All positioning data shall be continuously recorded and tracked electronically in a format that can be readily used to provide documentation of areas worked.

C. Tow/Tug Boats

1. All tow/tugboats used for propelling barges and other equipment shall be equipped with GPS navigational equipment, radar, corrected compass, at least two marine VHF radios approved for site use by the Owner, and depth-sounding equipment, which is to be maintained in good operating condition during each tow. The tow/tugboats used by the Contractor for this purpose shall be of a size adequate for pushing the anticipated load and have necessary reserve power for maneuvering with material barges under emergency conditions as well as for control of material barges during transit. Tugs and support boats should be operated in such a manner to limit resuspension of sediments.

D. Haul and Material Barges (If Applicable)

1. If the Contractor proposes to use haul barges, the Contractor shall select and identify the type of barge to be used in the DOP. No direct placement of dredged sediment is allowed within the beach nourishment area by barge dumping. The barge(s) shall be in good condition and certified to be seaworthy by the USCG.

2. Return water, if any, from barges shall be managed in accordance with the permit requirements (including but not limited to filtration of return water and barge freeboard requirements).

3. Sediment control measures will be maintained by the Contractor at all times; any problems identified by the Owner will be repaired immediately by the Contractor.

4. Load lines shall be clearly shown on the barge and loading shall not take the barge below the load lines.

5. The tug shall be of sufficient horsepower for moving the barge and maneuvering through the area and marine traffic encountered between the dredge area and the Beach Nourishment Area. Equipment must meet the permit and regulatory requirements of the South Coast Air Quality Management District, if applicable.

6. The Contractor shall provide the following information in the DOP on each dredge material barge that will be used:

a) Name of barge

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b) Length, beam, and molded depth of each barge

c) Dredge material capacity of barge

d) Hydrostatic data certified by a naval architect for determining barge displacement in short tons, per each 1 foot of displacement between loaded and light drafts; the haul barge shall have clear and distinct draft marks

e) Expected draft of barge loaded to capacity with dredged material

7. The Contractor shall load barge evenly to maintain the stability of the barge.

8. During dredging operations, measure and record on the Daily Report the tonnage of each barge. The tonnage reporting (displacement) will be documented and recorded upon the departure of the barge from the dredge area and upon arrival at the placement area.

9. During the entire period of work, provide and maintain sufficient spot or flood lights, as necessary, to permit the reading of the draft on the sides of material barges at bow and stern from the tow boat when visibility is impaired and at night, as approved by the Owner. Ensure that adequate time is allowed by the towboat captain for these readings to be obtained.

Include Tonnage Report Logs within the Daily Report.

E. Discharge Pipeline

1. If a discharge pipeline is used, propose the location of the discharge pipeline path to the Owner in the DOP. The Contractor shall submit for approval the identification and location of the discharge pipeline.

2. Pipeline Restrictions. Routing or storing of discharge pipeline will avoid dunes, dune vegetation, and naturally occurring beach debris.

3. Beach Access Ramp. Regarding any discharge pipeline laid on the beach surface, provide access ramps over the discharge pipeline at not more than 300-foot intervals to provide access for emergency vehicles to the beach, unless otherwise authorized or directed by the Owner. Ramps are to be a minimum 15 feet wide and constructed with sand from the adjacent area.

Contractor shall determine whether to use a steel plate or other cover on top of the access ramp to protect the pipeline. No ramps to be constructed across the vegetated areas, or the least tern area. Maintain and protect the discharge pipeline and ramps. The discharge pipeline to be free from holes, and joints to be watertight outside the designated limits of the placement area.

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4. Pipeline in waters of the U.S. (both floating and submerged) are to be clearly identified and marked with USCG standard buoys and lights to comply with USCG codes.

F. Booster Pump

1. If using a booster unit, mount on rubber to reduce vibration, equip with sufficient muffler system to reduce both the noise and odor, and vent the blower toward the ocean to minimize the noise level. Fully enclose the booster unit to a height not less than 6 feet, with a chain-link fence if the booster pump is not mounted on a barge.

G. Vessel Aids to Navigation (Lighting and Buoys)

1. The Contractor shall conform to all applicable regulatory (i.e., USCG) and Owner requirements for vessel lighting and buoys. Provide lights for floating equipment such as dredge plant, pipelines and material barges during periods of restricted visibility. If required per USCG, lights must also be provided for buoys, resuspension controls, or other activity markers that could endanger or obstruct navigation. Lights shall be provided for equipment being used to perform the work, even when not in use.

2. The Contractor will provide lights for work that is approved during non-daylight hours, defined as the period beginning 30 minutes before sunset and ending 30 minutes after sunrise. This will consist of providing, installing, operating, maintaining, moving, and removing portable light towers and equipment-mounted lighting fixtures for the duration of all dredging operations occurring during non-daylight hours over the water.

3. The Contractor shall set, then remove upon the Owner’s acceptance completion of work, all aids to navigation required for this Contract.

4. The Contractor shall furnish to the Owner, as part of the DOP, and upon regulatory agency request, a sketch showing the location of lights, buoys, and other marking devices being used during dredging operations over water and at the Beach Nourishment Area. The Contractor shall update this sketch as often as required to reflect actual conditions.

H. Construction Lighting

1. The Contractor will provide lights in accordance with City of Long Beach ordinances for work that is approved during non-daylight hours, defined as the period beginning 30 minutes before sunset and ending 30 minutes after sunrise. This will consist of providing, installing, operating, maintaining, moving, and removing portable light towers and equipment-mounted lighting fixtures for the duration of all land-based operations occurring

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during non-daylight hours at the Beach Nourishment Area and staging areas.

3.02 MOBILIZATION AND DEMOBILIZATION

A. Mobilization and demobilization to be conducted in accordance with Section 01 71 13, Mobilization and Demobilization.

3.03 DREDGING LIMITS

A. Order and Sequencing of the Work

1. Material located within EC-DU1 must be dredged and placed at the Beach Nourishment Area first, followed by the remainder of the dredge footprint as shown in the Drawings. Material from EC-DU1 shall be buried under material from the remainder of the dredge footprint.

2. Other than performing the dredging and placement of material from EC- DU1 first, it is not the intent of these Specifications to dictate the order of Work. The design has been based on sequencing considering working within an active navigational channel and recreational beach to enable a logical progression of the Work to its earliest completion.

B. Dredging Along Existing Jetty Toes

1. The Contractor shall segregate any Debris from any sediment prior to transport to the Beach Nourishment Area.

2. The Contractor shall complete cleanup pass dredging at the toe of slope a minimum of one week after achieving the required dredge depth, as necessary, to address sloughed material.

3. The Contract Documents indicate the Limits of Dredging as well as offset requirements from the jetty.

C. Required Limits. Material shall be dredged within the required dredging limits as shown on the drawings and as described below to achieve the project objective.

1. Limit of Required Dredging. Dredging shall be completed to the lines and elevations indicated on the drawings. If high spots remain above the Required Dredge Elevation following the review of a Progress Survey, Contractor shall immediately initiate corrective action to remove such high spots to the satisfaction of the Owner.

2. Side Slopes. Along the dredge prism edge adjoining the Alamitos Channel, the Contractor is required to dredge Side Slopes. The slopes are expected to naturally assume a stable inclination over time as material

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moves to attain a natural angle of repose. The Contractor is required to remove any material that sloughs from these Side Slopes into the dredge limits if that material protrudes above the Required Dredge Elevation.

Material from the Side Slopes (where dredged or through sloughing) is payable above the Side Slope limits shown on the drawings and includes one foot of Payable Overdepth. Note that the Side Slope inclination shown may not be the natural angle of repose encountered during dredging. Any sloughing that propagates from beyond or flatter than this slope inclination, and which needs to be removed from the required dredge area, will not be payable volume, and shall instead be incidental to the Contractor’s dredging price. Sloughing Side Slopes shall not be the basis for claims against the Owner.

3. Eelgrass or Caulerpa. Dredging in areas of eelgrass or Caulerpa is not permitted. Areas identified with eelgrass and/or Caulerpa must be marked and avoided during dredging. If required by the permits, best management practices, such as silt curtains shall be deployed.

3.04 DREDGING OPERATIONS

A. Notification. The Contractor shall notify the Owner a minimum of two (2) weeks prior to the proposed start of any dredging. Dredging shall not start until the Owner approves the start date and the Contractor Work Plan (CWP).

B. Misplaced Material. Should the Contractor (during the execution of the work) lose, dump, throw overboard, sink, or misplace any material, dredge, machinery, or appliance, the Contractor shall promptly recover and remove the same without additional cost to the Owner. This action may also be a violation of permit conditions, which prohibit the loss of material during transport to the placement area. The Contractor shall give immediate verbal notice, followed by written confirmation, of the description and location of misplaced material to the Owner.

C. Water Quality. The Contractor shall be responsible for all means and methods required for controlling and maintaining water quality standards during dredging and placement operations. The Contractor shall minimize turbidity and loss of resuspended sediments during dredging and transport operations and adhere to the Section 401 Water Quality Certification requirements and USACE permit requirements, subject to monitoring by the Owner.