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SECTION 35 20 23

DREDGING

PART 1 GENERAL

1.1 SCOPE

The work covered by this section consists of furnishing all labor, materials, and equipment, andperforming all excavation and disposal of all material as specified herein or indicated on the drawings.This scope also includes all necessary measures for protection of the environment. Environmentalprotection requirements under this contract are as important to overall completion of the work as othertechnical aspects. Failure to meet the requirements of these specifications for environmental protectionmay result in work stoppages or termination for default. No part of the time lost due to any such workstoppages shall be made the subject of claims for extensions of time or for excess costs or damagesby the Contractor. If the Contractor fails or refuses to promptly repair any damage caused by violationof the provisions of these specifications, the County may have the necessary work performed andcharge the cost thereof to the Contractor.

1.2 REFERENCES

The publications listed below form a part of this specification to the extent referenced. Thepublications are referred to in the text by basic designation only.

U.S. ARMY CORPS OF ENGINEERS (USACE) EM 385-1-1 (2008; Change 1-2010; Change 3-2010; Errata 1-2010) Safety and Health Requirements ManualVSTAR Global Positioning System SurveyingUSACE EM 1110-1-2909 (1998; Chg 2) Geospatial Data and SystemsUSACE EM 1110-2-1003 (2002) Hydrographic SurveyingStandards, Chapters 177, 472, 61G17 TRI-SERVICE STANDARDS (TSS)TSS (2006) A/E/C CADD Standards

USACE Engineer Manuals can be accessed at:http://140.194.76.129/publications/eng-manuals/

1.3 SUBMITTALS

Approval by County or its designee is required for submittals with a "G" designation; submittals nothaving a "G" designation are for information only. The following shall be submitted in accordancewith Section 01 33 00 SUBMITTAL PROCEDURES:

01 Preconstruction Submittals

Notice of Intent to Dredge

Prior to commencement of work on this contract, the Contractor shall notify theCommander, Seventh Coast Guard District of his intended operations to dredge andrequest that it be published in the Local Notice to Mariners. This notification must be given

in sufficient time so that it appears in the Notice to Mariners at least two weeks prior to thecommencement of this dredging operation. A copy of the notification shall be provided tothe County/Engineer.

Relocation of Navigation Aids

The Contractor shall not remove, change the location of, obstruct, willfully damage, makefast to, or interfere with any aid to navigation. Within 7 calendar days following receipt ofNotice of Award, the Contractor shall notify the Commander, Seventh Coast Guard District,Miami, Florida, of his plan to dredge adjacent to any aids which require relocation to

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facilitate dredging. The notification shall be sent via Fax to 305-415-6757, ATTN: Mr. JoeEmbres. This notification shall be immediately followed by a formal written request with acopy to the Contracting Officer. The Contractor shall also contact the U.S. Coast Guard,305-415-6730, for information concerning the position to which the aids will be relocated.

02 Shop Drawings

Construction and Grade Stakes Recovery Plan; G

The Contractor shall submit a Construction and Grade Stakes Recovery Plan to theCounty/Engineer 10 days after Notice of Award and concurrent with the preconstructionmeeting. The Plan will outline the steps that the Contractor will implement to recover all thestakes used on the project. This Plan will include the use of an inventory log that will bemade available for review by the appropriate County personnel.

03 Certificates

Grade Stake Recovery; G

After completion of the project, the Contractor shall provide a letter to the County/Engineer

certifying that all grade stakes have been recovered in accordance with the Contractor'sapproved Construction and Grade Stake Recovery Plan.

Electronic Tracking System Data

Furnish required discs, CD-ROM, and charts to the County/Engineer.

Equipment and Performance Data

Furnish proof of electronic positioning equipment calibration to the County/Engineer.

Historical Period Shipwreck Sites

The Contractor shall immediately notify the County/Engineer if any shipwreck, artifact, orother objects of antiquity that have scientific or historical value, or are of interest to thepublic, are discovered, located, and/or recovered.

Surveys

Hydrographic surveys to determine the volume of material removed under this Contract willbe performed by the County/Engineer. The County/Engineer will perform a before-dredging survey (BD) in order to provide updated bathymetry data in the areas to bedredged. The County/Engineer will also perform interim pay surveys and a final after-dredging (AD) survey to ensure adequate dredging to the required lines and grades.Interim pay surveys will be provided approximately every 10 days. The Contractor shallgive 7 days advance notice, in writing, to the County/Engineer of the need for a before-dredging survey or after-dredging survey for final acceptance.

Daily/Monthly Report of Operations

The Contractor shall submit one copy of a Daily Report of Operations for each dredgeand/or unloader working. This report shall be submitted on a daily basis and not in groups(groups = multi-days reports packaged together at one time). In addition to the daily report,the Contractor shall prepare a Monthly Report of Operations for each month or partialmonth's work. The monthly report shall be submitted on or before the 7th of each month,consolidating the previous month's work. Upon completion of the job, the Contractor shall

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submit a consolidated job report, combining the monthly reports.

Additionally, one copy of the form(s) shall be maintained by the Contractor on the dredge(s)for inspection purpose. Further instructions on the preparation of the reports will befurnished at the Preconstruction Conference.

Misplaced Material

The Contractor shall notify the U.S. Coast Guard Marine Safety Office of any misplacedmaterial.

Declaration of Inspection Stateside

Refer to paragraph FUEL OIL TRANSFER OPERATIONS below for submittal.

1.4 DREDGING RESTRICTIONS

1.4.1 Order of Work

Due to the dynamic shoaling nature of St. Lucie Inlet, the first order of work shall be "Area to beDredged" marked on plans for Entrance Channel Cut-1 followed by transition area or as directed by theCounty/Engineer. The Contractor shall access the impoundment basin adjacent to the entrancechannel as directed by the County/Engineer and complete a portion or all of the Dredge Option(Alternatives A-G) areas only if directed by the County/Engineer.

1.4.2 Restriction

The Contractors dredging plant and placement equipment shall be of sufficient size and type to meetthe requirements of the work within the time specified by the Contract. Hopper dredges shall beprecluded from this work. Mechanical (bucket) dredging or hydraulic dredging are allowed.

1.5 SPECIAL INSTRUCTIONS

Dredging of in situ rock is not required; but if encountered, the location and extent of any in siturockabove grade or required depth shall be reported to the County/Engineer.

1.6 PUMPING OF BILGES

Contractors are warned that pumping oil or bilge water containing oil into navigable waters, or intoareas which would permit the oil to flow into such waters, is prohibited by Section 13 of the River andHarbor Act of 1899, approved 3 March 1899 (30 Stat. 1152; 33 U.S.C. 407). Violation of thisprohibition is subject to the penalties under the referenced Acts.

1.7 HISTORICAL PERIOD SHIPWRECK SITES

If any shipwreck, artifact, or other objects of antiquity that have scientific or historical value, or are

of interest to the public, are discovered, located, and/or recovered, the Contractor acknowledgesthat:

a. The site(s), articles, or other materials are the property of the State of Florida, with titlevested in the Department of State, Division of Historical Resource; and that,b. He will immediately notify the County/Engineer.

1.8 UTILITY CROSSINGS

1.8.1 General

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It is the Contractor's responsibility to investigate the location of all utility crossings. The Contractorshall take precautions against damages which might result from his operations in the vicinity of theutility crossings. If any damage occurs as a result of his operations, the Contractor will be required tosuspend dredging until the damage is repaired and approved by the Engineer and the County. Costsof such repairs and downtime of the dredge and attendant plant shall be at the Contractor'sexpense.

1.9 PERMITS

The Contractor's attention is directed to the Permits attached as exhibits to this document and theparagraph PERMITS AND AUTHORIZATIONS of Section 01 41 00 ENVIRONMENTALPROTECTION.

1.10 FUEL OIL TRANSFER OPERATIONS

In accordance with U.S. Coast Guard regulations (33 CFR 156.120), couplings used in fuel oil transferoperations on any vessel with a capacity of 250 or more barrels of oil shall be either a bolted or full-threaded connection; or a quick-connect coupling approved by the Commandant; or an automatic back-pressure shutoff nozzle used to fuel the vessel. An executed fuel oil transfer (Declaration) form signedby the tanker operator shall be submitted to the County/Engineer for each refueling operation. The U.S.Coast Guard shall also be notified prior to any refueling.

1.11 SIGNAL LIGHTS

The Contractor shall display signal lights and conduct operations in accordance with the GeneralRegulations of the Coast Guard governing lights and day signals to be displayed by towing vessels withtows on which no signals can be displayed, vessels working on wrecks, dredges, and vessels engagedin laying cables or pipe or in submarine or bank protection operations, lights to be displayed on dredgepipe lines, and day signals to be displayed by vessels of more than 65 feet in length moored oranchored in a fairway or channel, and the passing by other vessels of floating plant working innavigable channels, as set forth in Commandant U.S. Coast Guard Instruction M16672.2, NavigationRules: International-Inland (COMDTINST M16672.2), or 33 CFR 81 Appendix A (International) and 33CFR 84 through 33 CFR 89 (Inland) as applicable.

1.12 NOTICE TO MARINERS -- DREDGING CONTRACTS

Should the Contractor, during operations, encounter any objects on the channel bottom which couldbe a hazard to navigation, the Contractor shall immediately notify the County/Engineer as to thelocation of said object and shall provide any other pertinent information necessary for the ContractingOfficer to prepare and issue a Notice to Mariners.

1.13 FINAL CLEANUP

Final cleanup shall include the removal of all the Contractor's plant and equipment either for disposalor reuse. Plant and/or equipment and/or materials to be disposed of shall only be disposed in amanner and at locations approved by the Contracting Officer. Unless otherwise approved by the

Contracting Officer, the Contractor will not be permitted to abandon any equipment in the disposalarea or other areas adjacent to the worksite.

a. Failure to promptly remove all plant, pipeline, equipment, and materials upon completion ofthe dredging shall be considered a delay in the completion of the final cleanup anddemobilization work. In such case, the County will exercise its right as stated in Article 17 ofthe AGREEMENT to remove any plant and/or equipment and/or materials at the Contractor'sexpense.

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1.14 WORK VIOLATIONS

Work done in violation of these specifications or a verbal or written stop order of the County will beconsidered as unsatisfactory progress for purposes of progress payments (in accordance with Article5 of the AGREEMENT).

PART 2 PRODUCTS (NOT APPLICABLE)

PART 3 EXECUTION

3.1 NOTIFICATION OF COAST GUARD

3.1.1 Navigation Aids

Navigation aids located within or near the areas required to be dredged will be removed, ifnecessary, by the U.S. Coast Guard in advance of dredging operations. The Contractor shall notremove, change the location of, obstruct, willfully damage, make fast to, or interfere with any aid ofnavigation.

3.1.2 Dredging Aids

The Contractor shall obtain approval from the U.S. Coast Guard for all buoys, dredging aid markers tobe placed in the water, and dredging aid markers affixed with a light prior to the installation. Dredgingaid markers and lights shall not be colored or placed in a manner that they will obstruct or be confusedwith navigation aids.

3.2 WORK AREA

The Contractor will be permitted to exclude the public from the work areas in the immediate vicinity ofhis dredging, transporting, and disposal operations. The Contractor shall prevent public access to thedischarge end of the pipeline. The Contractor shall erect, maintain, and move as necessary, arestrictive barrier around the discharge of the hydraulic pipeline. The barrier shall be constructed so asto prevent the public from approaching the discharge from any direction closer than 40 feet. The

Contractor shall post signs in a conspicuous location with the wording "DANGER - HIGH PRESSUREDISCHARGE FROM DREDGE". Enforcement shall be the Contractor's responsibility at no additionalcost to the County. The enforcement shall be coordinated with local enforcement agencies and will besubject to approval of the County. Additionally, the Contractor shall place a safety person at thedischarge end of the disposal pipeline. The safety person shall be present at all times during dischargeoperations and will maintain radio communication between the dredge and the disposal operation.

3.2.1 Access

The Contractor shall be responsible for providing and maintaining access necessary for his equipmentand plant to and from the work site, mooring area, and disposal area. The Contractor shall ascertainthe environmental conditions which can affect the access such as climate, winds, currents, waves,depths, shoaling, and scouring tendencies.

3.2.2 Protection of Existing Waterways

The Contractor shall conduct his operations in such a manner that material or other debris are notpushed outside of dredging limits or otherwise deposited in existing side channels, basins, dockingareas, or other areas being utilized by vessels. The Contractor will be required to change his method ofoperations as may be required to comply with the above requirements. Should any bottom material orother debris be pushed into areas described above, as a result of the Contractor's operations, thesame must be promptly removed by and at the expense of the Contractor to the satisfaction of theEngineer and the County.

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3.2.3 Adjacent Property and Structures

No dredging will be permitted within 25 feet of any structure. Any damage to private or public propertyor structures resulting from the disposal or dredging operations shall be repaired promptly by theContractor at his expense. Any damage to structures as a result of Contractor's negligence will resultin suspension of dredging and require prompt repair at the Contractor's expense as a prerequisite tothe resumption of dredging.

3.2.4 Subaqueous Cable Crossings

The Contractor shall be responsible for verifying the locations and depths of all utility crossings andtake precautions against damages which might result from his operations, especially the sinking ofdredge spuds and/or anchors into the channel bottom, in the vicinity of utility crossings. If any damageoccurs as a result of his operations, the Contractor will be required to suspend dredging until thedamage is repaired and approved by the County and the Engineer. Costs of such repairs anddowntime of the dredge and attendant plant shall be at the Contractor's expense.

3.3 DISPOSAL OF EXCAVATED MATERIAL

3.3.1 General

Material excavated shall be transported to and deposited in the beach disposal areas designated onthe drawings. The average distance to which the material will have to be transported is approximately4.5 miles and the maximum distance will be approximately six miles.

3.3.2 Beach Disposal

Dredged material from St. Lucie Entrance Channel Cut-1, transition area, and the impoundment basinshall be placed in Hobe Sound National Wildlife Refuge (HSNWR) Beach Disposal Area (D/A) asshown on the contract drawings. The dredged material shall be placed to the sections and limits asshown on the drawings to the extent of the dredged material. Beach placement equipment, pipeline,etc. shall utilize either the existing 50-foot easement from St. Lucie Inlet through St. Lucie Inlet State

Park to Hobe Sound Wildlife Refuge as shownor

by barging dredged material through the IntracoastalWaterway to existing 20-foot, beach access easement and unloading area located at Peck's Lakebeach monument R-064 as shown on contract drawings. Refer to contract drawings for locations. TheContractor shall utilize existing access easements to route equipment and pipeline to the beachdisposal area. All beach placement work shall be conducted within the limits of the disposal area (SeeSpecification & Plans).

3.3.2.1 Order of Placement

Dredged material shall be placed in HSNWR D/A between R-061 and R-075 completely filling thetemplate until all dredged material has been placed to the sections and limits shown on the contractdrawings. The Contractor shall begin placement at the north end of the site, at DEP monument R-061,and proceed south toward DEP monument R-075. Mechanical operations shall be permitted to beginplacement from the 20' pipeline corridor "A" located near DEP monument R-064 and fill north to DEPmonument R-061 until the template is full. The Contractor shall then proceed from the 20' pipelinecorridor "A" south toward DEP monument R-075. If more capacity is required, the Contractor is thendirected to move his/her disposal operation to the south and progress south until all the material isexhausted.

Prior to placement of fill, the Contractor shall remove from the site of the work all snags, driftwood, andsimilar debris lying within the foundation limits of the beach fill section. All materials removed shall bedisposed of in areas provided by and at the expense of the Contractor and approved by theCounty/Engineer. Grading and other construction equipment will not be permitted outside the easement

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lines shown on the drawings except for ingress and egress to and from the site as approved by theCounty/Engineer and property owner(s).

The excavated material shall be placed and brought to rest on the beach to the lines, grade, and crosssections indicated on the drawings, unless otherwise provided for herein or directed by theCounty/Engineer. The Contractor shall not stockpile pipe or any other equipment or debris on thebeach except as approved by the County/Engineer. The beach is subject to changes and theelevations on the beach at the time the work is done may vary from the elevations shown on thedrawings. The County/Engineer reserves the right to vary the width or grade of the berm from the linesand grade shown on the plans in order to establish a uniform beach for the entire length of the project.The beach disposal section shown on the drawing is for the purpose of estimating the theoreticalamount of fill needed and will be used by the County/Engineer in making any change in the lines andgrade. The Contractor may not be able to achieve the exact disposal area shown on the drawings. Heshall, however, be required to move the pipeline discharge to another part of the disposal area when hehas discharged the amount of dredged materials in an area that would produce that cross section.Earthen pedestrian access ramps shall be provided across the dredge discharge pipeline at 200-footintervals. The Contractor shall monitor the dredge and fill operations and shall notify theCounty/Engineer if and when the quantity to be dredged appears to be excessive for the designatedbeach disposal area. The Contractor will not be required to dress the fill below the water line to theslope shown but will be required to do the dressing specified in subparagraph "Dressing" below.

3.3.3 Grade Stakes

Grade stakes shall be metal pipes that can be completely removed intact by the Contractor afterplacement of the fill. Grade stakes shall be of sufficient length to protrude above the final bermelevation and facilitate their extraction.

3.3.4 Temporary Longitudinal Dikes

Temporary longitudinal dikes and spreader and/or pocket pipe shall be used to prevent gullying anderosion of the beach, and fill and to retain the fill on the beach within the limits of the fill cross section,and to minimize turbid discharge into state waters. As the work progresses, dikes or mounds shall beconstructed along the beach to direct the pipeline discharge longitudinally along the beach to avoid

transverse gullying directly from the discharge point to the ocean, and to build the new berm to designgrade. Longitudinal dikes shall be constructed to the appropriate size required to meet water qualitystandards, to build to the required lines and grades, and to keep material within the toe-of-fill. TheContractor will not be held responsible for erosion caused by waves after the beach fill has beensatisfactorily placed. No undrained pockets shall be left in any fill during or upon completion of thework. The Contractor shall not permit wastewater to flow landward of the fill section or water to pondbetween the fill and upland. Groins, bulkheads, revetments, seawater pipe structures, and otherstructures within the fill section shall be protected by the Contractor to prevent damage thereof by theContractor's operations. Any damages assessed as a result of any of the above items shall be at theContractor's expense.

3.3.5 Rehandled Materials

Any material that is rehandled or moved and placed in its final position by methods other than hydraulic

shall be placed in horizontal layers not to exceed three (3) feet in thickness. Compaction of the layersshall not be required. The Contractor shall schedule his operations to take advantage of tides so thatfilling is done in the dry or as directed.

3.3.6 Dressing

Final dressing shall take place as convenient to the Contractor to complete the work by 30 April, 2012.

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At this time all evidence of haul road or pipeline shall be removed and the fill shall be graded anddressed so as to eliminate any undrained pockets and abrupt humps and depressions in the beach fillsurfaces and as necessary to comply with subparagraph "Tolerances" below. Grade stakes used in theplacement of the fill shall be removed intact, without breaking. All dikes shall be completely degraded.The bank caused by wave forces shall be graded down to a slope no steeper than 1 vertical on 10horizontal for HSNWR D/A.

3.3.7 Tolerances

A tolerance of one half (0.5) foot above the prescribed berm grade and slopes above the wavezone will be permitted in the final beach surface. Excess material above this tolerance may be leftin place or be required to be removed at the discretion of the County/Engineer.

3.3.8 Debris Removal

The Contractor shall clean and remove from the beach disposal areas all debris that has been placedon the beach as a result of the disposal operation. The debris will be disposed of in a locationprovided by the Contractor and accepted by the County/Engineer. The Contractor shall continuouslymonitor the material as it is placed on the beach. Any dredged material that is obviously notcompatible with beach placement (such as significant amounts of large shells, rock, coarse gravel or

silt) shall be immediately removed and reported to the County/Engineer.

3.3.9 Pipeline Accesses

Refer to contract drawings for location of a 20-foot pipeline access route from Peck Lake to the beachdisposal area for dredged material transported via Intracoastal Waterway from St. Lucie Inlet. Thisaccess will be cleared by the County upon Notice of Award if the project is to be executed using bargetransport of material. Access is also available via an overland 50-foot pipeline easement from St. LucieInlet through State Park to HSNWR D/A as shown on the contract plans. The overland 50-footeasement continues south of the State Park property line with the centerline at the seaward edge of theexisting dune.

3.3.10 Barges

Water and dredged materials shall not be permitted to overflow or spill out of barges while transportingto the disposal site(s). Failure to repair leaks or change the method of operation which is resulting inoverflow or spillage will result in suspension of dredging operations and require prompt repair orchange of operation to prevent overflow or spillage as a prerequisite to the resumption of dredging.Logs will be kept documenting the work performed by each barge and will be included in the dailyreports.

3.3.11 Electronic Positioning Equipment

The contractor shall have electronic positioning equipment which continuously measures the verticaland horizontal location of the cutterhead, drag-arms, dustpan or clamshell at all times duringoperations. The horizontal positioning equipment shall be installed on the dredge so as to monitor theactual location of the dredge equipment and be interfaced with the depth monitoring device.Horizontal accuracy for dredge positioning shall be at least 3.0 feet. Vertical accuracy for the dredgedepth monitoring shall be at least 0.5 foot. This equipment shall provide a permanent record of theequipments position referenced to State Plane Coordinates and NAVD88. As a part of the final report,the contractor shall provide a daily record of the position of the dredge equipment which includes thedredge area limits and any established environmental buffer zones referenced to state planecoordinates and NAVD88.

3.3.12 Placing of Dredged Material

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During placement of dredged material in the disposal areas, the Contractor will be required to provideconstant radio contact between the dredge/material offloader and the disposal areas. This will enablethe Contractor's personnel at the disposal areas to immediately notify the dredge or offloadingequipment in the event of pipeline failure. In the event of pipeline failure, the dredging operations shallbe immediately suspended and require prompt repair of the dike or pipeline as a prerequisite to theresumption of dredging.

3.3.13 Dredge Pipelines

3.3.13.1 Dredge Discharge Pipeline

The Contractor shall plainly mark the pipeline access routes with conspicuous stakes, targets and/orbuoys to be maintained throughout the contract operations. A tight dredge discharge pipeline shall bemaintained to prevent spilling of dredged material or dredge water outside of the disposal area. TheContractor shall provide and maintain radio communication between the dredge and the disposal areasand the dredge and the County or designee. The pipeline shall be inspected at least twice daily forleaks. Failure to immediately repair leaks in the discharge pipeline will result in suspension of dredgingoperations and require prompt repair of pipeline as a prerequisite to the resumption of dredging. Anydamage to private or public property resulting from the Contractor's operations shall be repaired by theContractor at his expense.

3.3.13.2 Submerged Pipeline

In the event the Contractor elects to submerge his pipeline, the pipeline shall rest on the bottom, andthe top of the submerged pipeline and any anchor securing the submerged pipeline shall be no higherthan the required project depth for the channel in which the submerged pipeline is placed. Should theContractor elect to use a pipeline material which is buoyant or semi-buoyant, such as PVC pipe orsimilar low density materials, the Contractor shall securely anchor the pipeline to prevent the pipelinefrom lifting off the bottom under any conditions. The Contractor shall make daily inspections of thesubmerged pipeline to ensure buoyancy has not loosened the anchors. The Contractor shall remove allanchors when the submerged pipeline is removed. The location of the entire length of submergedpipeline shall be marked with signs, buoys, lights, and flags conforming to U.S. Coast Guardregulations.

3.3.13.3 Floating Pipeline

Should the Contractor's pipeline not rest on the bottom, it will be considered a floating pipeline andshall be visible on the surface and clearly marked. In no case will the Contractor's pipeline be allowedto fluctuate between the surface and the bottom, or lie partly submerged. Lights shall be installed onthe floating pipeline as required in paragraph SIGNAL LIGHTS above. The lights shall be supportedeither by buoys or by temporary piling, provided by the Contractor and approved by theCounty/Engineer. Where the pipeline does not cross a navigable channel, the flashing yellow all-around lights shall be spaced not over 50 feet apart, unless closer spacing is required by U.S. CoastGuard personnel, in which case the requirements of the U.S. Coast Guard shall govern, at noadditional cost to the County.

3.3.14 Booster Pumps

Any booster pumps installed by the Contractor shall be located at least 300 feet from any residential-type building or house. Booster pumps, their prime movers, and any auxiliary equipment shall be fittedor equipped with mufflers, noise control enclosures, or other engineering noise control methods,measures, and features such that steady noise emanating from this equipment does not exceed 85decibels on the A scale at slow response, and impulsive noise does not exceed 140 decibels. Suchitems shall be maintained throughout the course of the work. In addition, all localordinances/regulations regarding noise shall be adhered to.

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3.3.15 Misplaced Materials

Materials deposited above the maximum indicated elevation or outside of the disposal areatemplate shown will require the regrading or removal of such materials at the Contractor's expense.Excess material above this tolerance may be left in place or be required to be removed at thediscretion of the County/Engineer.

The Contractor will not be held responsible for erosion caused by waves after the material has beensatisfactorily placed. In addition, the Contractor must notify the County/Engineer and the EnvironmentalProtection Agency within 24 hours of a misplaced dump or any other violation of the Site Monitoringand Management Plan.

3.3.16 Suitable Material for Beach Placement

Mateirals deposited on the beach shall be compatible with native/exisitng material on the beach. The

contractor will monitor the quality of material being dredged and deposited on the beach and take

whatever measures and precautions necessary to ensure non-compatible material is not placed on the

beach. Although no fill tests or analysis is required, the contractor should carefully observe the fill and

note any marked change in character. The Engineer should be notified immediately if any such change

is noted. At the first sign non-compatible material is being dredged, the contractor will cease dredgingin the area of non-compatible material and adjust the dredge location until dredging of beach

compatible material is resumed.

The Florida Department of Environmental Protection has determined that: beach compatible fill is

material that maintains the general character and functionality of the material occurring on the beach

and in the adjacent dune and coastal system. Such material shall be predominately of carbonate,

quartz or similar material and be similar in color and grain size distribution to the material in the existing

coastal system at the disposal site and in general shall not contain:

1. Greater than 5 percent, by weight, silt, clay or colloids passing the #230 sieve (4.0);2. Greater than 5 percent, by weight, fine gravel retained on the #4 sieve (-2.25);3. Coarse gravel, cobbles or material retained on the 3/4 inch sieve in a percentage or size

greater than found on the native beach;4. Construction debris, toxic material or other foreign matter; and5. Not result in cementation of the beach.

If rocks or other non-specified materials appear on the surface of the filled beach in excess of 50% ofbackground in any 10,000 square foot area, then surface rock should be removed from those areas.These areas shall also be tested for subsurface rock percentage and remediated as required. If thenatural beach exceeds any of the limiting parameters listed above, then the fill material shall not exceedthe naturally occurring level for that parameter

3.4 REQUIRED DEPTH, ALLOWABLE OVERDEPTH, AND SIDE SLOPES

3.4.1 Required Depth

The material actually removed from the designated areas to be dredged, to a depth of not more thanthe required depth shown on the drawings, will be estimated and paid for in accordance with theprovisions contained in the subparagraphs "Measurement" and "Payment" of Section 01 11 00SUMMARY OF WORK.

3.4.2 Allowable Overdepth

To cover the inaccuracies of the dredging process, material actually removed from the designatedareas to be dredged, to a depth below the required depth of not more than the allowable overdepth

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shown on the drawings, will be measured and paid for in accordance with the provisions containedin the subparagraphs "Measurement" and "Payment" of Section 01 11 00 SUMMARY OF WORK.

3.4.3 Side Slopes

Although dredging of side slope material may be necessary to provide the required project channeldimensions (depth and width), the side slopes shown on the drawings are provided for paymentpurposes only. Side slopes may be formed by box cutting, step cutting, or dredging along the sideslope. Material actually removed, within the limits approved by the County/Engineer, to provide forfinal side slopes not flatter than that shown on the contract drawings, but not in excess of theamount originally lying above this limiting side slope, will be measured and paid for in accordancewith the provisions contained in subparagraphs "Measurement" and "Payment" of Section 01 11 00SUMMARY OF WORK.

3.4.4 Excessive Dredging

Materials taken from beyond the limits as described in subparagraphs "Allowable Overdepth" and"Side Slopes" above, will be deducted from the total amount dredged as excessive overdepth

dredging, or excessive side slope dredging, for which payment will not be made. Nothing hereinshall be construed to prevent payment for the removal of shoals performed in accordance withapplicable provisions of the paragraphs FINAL EXAMINATION AND ACCEPTANCE or SHOALINGof this Section.

3.4.5 Areas to be Dredged

Based on information currently available to the County, areas known to require dredging are depictedon the drawings as hatched areas. The actual areas to be dredged may vary from the hatched areasshown in the drawings. In order to provide the required project dimensions within and throughout theproject limits shown on the drawings, the Contractor shall remove material located within the projectlimits as directed by the County/Engineer, regardless of whether the material is located in a hatchedarea or not. Payment for all material dredged will be made at the applicable contract unit price.3.5

SURVEYS

3.5.1 General

The County/Engineer shall be notified, in writing, 7 days in advance of the need for pre-and post-dredging surveys. Hydrographic surveys to determine the volume of material removed under thisContract will be performed by the County/Engineer. The County/Engineer will perform a before-dredging survey (BD) in order to provide updated bathymetry data in the areas to be dredged. TheCounty/Engineer will also perform interim pay surveys and a final after-dredging (AD) survey toensure adequate dredging to the required lines and grades. Interim pay surveys will be providedapproximately every 10 days.

All hydrographic surveys conducted shall follow the guidelines as referenced in the Corps ofEngineers Hydrographic Survey Manual EM 1110-2-1003, dated 01 January 2002, for navigationand Dredging Support Surveys, for soft bottom material. Electronic single beam cross sections,on 50-foot station intervals, will be utilized to compute the volume of material removed. Allelectronic echo sounders will operate nominally at 200 kHz.

3.5.2 Contractor Representative

The Contractor or his authorized representative will be notified when surveys are to be made. Allin-place measurement surveys and final acceptance surveys may be performed with arepresentative of the Contractor on board the survey platform during the full execution of the

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survey. The Contractor shall indicate to the County/Engineer per each survey if they willaccompany the survey crew(s). If the Contractor chooses to accompany the survey crew(s), theContractor's representative shall be fully knowledgeable in offshore construction subsurfacesurveying procedures, techniques, equipment, and horizontal and vertical calibration methods, andstate-of-the-art horizontal and vertical accuracy limitations. The Contractor's representative shallobserve and review, in progress, the adequacy and accuracy of the survey for in-place paymentpurposes, and for the potential existence of collusion, fraud, or obvious error in the data.

3.6 INSPECTION

The County/Engineer shall be notified prior to the establishment of horizontal control work (baselinelayout, ranges, station flags, shore-based control for EPS/RPS, etc.) and vertical control work (tidestaff(s), upland cross sections, construction elevations top/invert, maximum/minimum elevations ofdredged materials within disposal area(s), etc.), but the presence or absence of theCounty/Engineer shall not relieve the Contractor of his responsibility for proper execution of thework in accordance with the specifications. The Contractor will be required:

To furnish, on the request of the County or Engineer, the use of such boats, boatmen, laborers,and material forming a part of the ordinary and usual equipment and crew of the dredging plant asmay be reasonably necessary in inspecting and supervising the work. However, the Contractor will

not be required to furnish such facilities for the surveys prescribed in the paragraph FINALEXAMINATION AND ACCEPTANCE of this Section. To furnish, on the request of the County orEngineer suitable transportation from all points on shore designated by the County/Engineer to andfrom the various pieces of plant, and to and from the disposal area3.6.2 Failure to Comply

Should the Contractor refuse, neglect, or delay compliance with these requirements, the specificfacilities may be furnished and maintained by the County and the cost thereof will be deducted fromany amounts due or to become due the Contractor.

3.7 FINAL EXAMINATION AND ACCEPTANCE

3.7.1 Final Examination of Work

As soon as practicable and no later than 7 days after the completion of the entire work or anysection thereof (if the work is divided into sections) as in the opinion of the County/Engineer will notbe subject to damage by further operations under the contract, such work will be thoroughlyexamined at the cost and expense of the County by sounding or by sweeping, or both, asdetermined by the County/Engineer. Should any shoals, lumps, or other lack of contract depth bedisclosed by this examination, the Contractor will be required to remove same by dredging at thecontract rate of dredging.

The Contractor or his authorized representative will be notified when soundings and/or sweepingsare to be made and will be permitted to accompany the survey party. When the area is found to bein a satisfactory condition, it will be accepted finally. Should more than two sounding or sweepingoperations by the County over an area be necessary by reason of work for the removal of shoalsdisclosed at a prior sounding or sweeping, the cost of such third and any subsequent soundings orsweeping operations will be charged against the Contractor at the rate of $5,500 per day for eachday in which the Countys plant is engaged in sounding or sweeping and/or is enroute to or fromthe site or held at or near the said site for such operation.

3.7.2 Final Acceptance

Final acceptance of the whole or a part of the work and the deductions or corrections of deductionsmade 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

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payment of the retained percentages of the whole or any part of the work.

3.8 SHOALING

If, before the contract is completed, shoaling occurs in any section previously accepted, includingshoaling in the finished channel because of the natural lowering of the side slopes, re-dredging atcontract price, within the limits of available funds may be done if agreeable to both the Contractor andthe County/Engineer.

3.9 CONTINUITY OF WORK

No payment will be made for work done in the navigation channel until the full depth required under thecontract is secured in the whole of the area, unless prevented by in-situ rock or otherwise approved inwriting by the County/Engineer. The navigation channel is the first priority. No payment will be madefor dredging in the transition and impoundment areas until the navigation channel has been acceptedby the County/Engineer. Payment for work in adjacent excavation areas (transition area andimpoundment basin) will be made for work on completed sections (full depth required) on the basis ofvolume dredged at the discretion of the County/Engineer.

3.10 NOISE CONTROL

All hauling and excavating equipment and dredge/barges, boats, and tugs used on this work shall beequipped with satisfactory mufflers or other noise abatement devices. The Contractor shall conduct hisoperations so as to comply with all Federal, State and local laws pertaining to noise. The use of hornsand whistle signals shall be held to the minimum necessary in order to ensure as quiet an operation aspossible.

3.11 DREDGE CERTIFICATION

During dredging operations the Contractor's dredge shall have a current Certificate of Inspection issuedby the U.S. Coast Guard.

3.12 GENERAL DREDGING SAFETY REQUIREMENTS

3.12.1 Dredge Plant General Safety

The Contractor should familiarize himself with anticipated weather conditions in St. Lucie Inlet. Seaconditions with waves 3 feet in height or greater and ocean currents exceeding 3 knots can beanticipated frequently in the project area. Bidders are responsible for providing equipment andpersonnel capable of safely operating in the climate and conditions found in St. Lucie Inlet withoutexcessive weather delays and without risking health and human welfare.

3.12.2 Coast Guard Regulations

All vessels working in the inlet and the federal navigation channel shall operate in accordance with allapplicable Coast Guard regulations.

3.12.2 Certification of Attendant and Plant

All floating plant for dredging operations (to include, but not limited to, dredges, anchor barges, deckbarges, deck/work barges, tug boats, tenders, workboats, pump-out barges, derrick barges, andspider barges) shall have a current marine survey inspection certificate. The only exceptions to thisrequirement include pipeline support pontoons or floats and outboard skiffs under 16 feet in length.The certification shall have been issued by a licensed and accredited marine surveyor within theprevious 12 months. The marine surveyor must be accredited by either the National Association of

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Marine Surveyors or the Society of Accredited Marine Surveyors. No attendant plant that does nothave a valid certification shall be used on this contract. The certifications and inspection shall beappropriate for the intended use of the plant in all locations specified in this contract. Unless theCounty/Engineer decides otherwise, documentation of the inspection for each piece of plant shall beprovided prior to issuance of Notice to Proceed.

3.12.3 Minimum Tow-Boat Requirements

a. Towboats shall be of adequate size and horsepower to move any and all attendant and support plantagainst prevailing tides, currents, and winds during normal and severe weather conditions. Thetowboat(s) shall be available within the project work area at all times.

b. A towboat(s) of adequate size and horsepower to move the dredge(s) against prevailing tides,currents, and winds during normal and severe weather conditions shall be able to mobilize to the worksite, and move the dredge(s) to safe harbor with 4 to 6 hours of first notification.

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