Exhibit_A_Technical_Specifications_Clarifier_No._4_(revised).docx

TABLE OF CONTENTS

NWWRF Clarifier #4 Improvements Technical Specifications

SECTION 1 – GENERAL

1.01

1.02 1.03

1.04 1.05

1.06 1.07

1.08 1.09

1.10 1.11 1.12

1.13 1.14

1.15 1.16 1.17

1.18

1.19

1.20 1.21

1.22

1.23 1.24

LOCATION OF THE WORK SITE AND ACCESS SCOPE OF WORK

PLANS AND SPECIFICATIONS INSPECTION AUTHORITY PROJECT SCHEDULE PROJECT START TIME

STORM PREPAREDNESS PLAN MATERIALS AND EQUIPMENT MANUFACTURER

MATERIAL AND EQUIPMENT DELIVERY AND STORAGE SERVICE SERVICE OF MANUFACTURER'S REPRESENTATIVE

SPILL OR DISCHARGE OF WASTEWATER OR RECLAIMED WATER SEQUENCE OF OPERATION

FIELD OFFICE AND APPURTENANT STRUCTURES CONTRACTOR’S SIGN

MOBILIZATION WATER PURCHASES UTILITIES

SHOP, FIELD, AND LABORATORY TESTING SPECIAL CONSIDERATIONS FOR PLANT WORK PLANT SECURITY

SALVAGED MATERIAL PAYMENT TERMS CONTINGENCY ALLOWANCE

SECTION 2 – EXCAVATION AND BACKFILL

2.01 GENERAL

2.02 TRENCH SAFETY

2.03 WORK IN WETLANDS, MANGROVES, AND PRESERVATION AREAS

2.04 CLEARING AND GRUBBING

2.05 ROADWAY EXCAVATION

2.06 TRENCH EXCAVATION

2.07 STRUCTURE EXCAVATION

2.08 EXCAVATION OF UNSUITABLE MATERIAL

2.09 SHEETING, SHIELDING AND SLOPING

2.10 DEWATERING

2.11 BORROW MATERIAL

2.12 BEDDING MATERIAL

2.13 STRUCTURAL SLAB BEDDING

2.14 BACKFILL COMPACTION

2.15 BACKFILLING OF TRENCH

2.16 BACKFILLING STRUCTURES

2.17 BACKFILLING UNDER ROADWAYS

2.18 DISPOSING OF LEFTOVER MATERIAL

2.19 ADJACENT FACILITIES

2.20 TEMPORARY SUPPORTS

2.21 FLOWABLE FILL

SECTION 3 - PIPING MATERIALS: DUCTILE IRON PIPE

4.01 GENERAL

4.02 PIPE

4.03 FITTINGS

4.04 JOINTS - BURIED PIPE AND FITTINGS

4.05 JOINTS - EXPOSED PIPE AND FITTINGS

DIVISION 1 – GENERAL REQUIREMENTS

01 51 00 01 75 00

DIVISION 3

03 01 30

Temporary Utilities Checkout and Startup Procedures

Concrete Repairs

DIVISION 5 - METALS

DIVISION 6 – WOOD, PLASTICS, AND COMPOSITES

06 51 00 Glass Fiber and Resin Fabrications

DIVISION 7 – THERMAL AND MOISTURE PROTECTION

07 90 00 Joint Fillers, Sealants and Caulking

DIVISION 9 - FINISHES

09 90 00 Painting

DIVISION 26

26 05 05 Electrical System Requirements

DIVISION 40- PROCESS INTERCONNECTIONS

40 05 00 Basic Mechanical Requirements

DIVISION 46 – WATER AND WASTEWATER EQUIPMENT

SECTION 1 - GENERAL

1.01 LOCATION OF THE WORK SITE AND ACCESS

The general location of the proposed Work for the Project is as follows: Northwest Water Reclamation Facility 7500 26th Avenue North St. Petersburg, Florida 33710 Access to the Work site shall be over public streets and rights-of-way. Any damage to existing pavement or other surface improvements outside the Contract Pay Limits, attributable to the Contractor's activities, shall be restored to like-new condition by the Contractor at the Contractor's expense.

1.02 SCOPE OF WORK

The Work associated with the Project is to furnish and install the necessary equipment for the replacement of (1) Ovivo 135' diameter C4D-CMD type spiral blade clarifier mechanism, plus non-submerged and submerged components. No substitutions will be allowed. The essential portions of the proposed Work for the Project are summarized as follows:

· Demolition of the existing clarifier mechanism and associated apparatuses

· Tank interior to be brush blasted and repaired where necessary

· Tank interior to be blasted and recoated with epoxy coating system.

Recoating shall be from interior floor-wall joint, up the entire height of the vertical masonry wall, and terminate at the top of the wall cap. All surfaces within this zone shall be cleaned and prepared to meet coating manufacturer’s recommendations.

· New clarifier mechanism, including listed non-submerged and submerged components

· New walkway

· Tie-in to existing waste activated sludge (WAS) line.

· Installation of in-line grinder JWC Environmental grinder (Muffin Monster), control panel and electrical lines.

1.03 PLANS AND SPECIFICATIONS

Technical Specifications Sections 1 and 20 have been prepared specifically for this Project. Other Technical Specifications sections are City Standards and only the applicable portions of them govern the Work to be performed. Hazen Divisions 1, 3, 5, 6, 7, 9, 26, 40, and 46 have also been prepared specifically for this Project. Where the Plans and Specifications are not in agreement, the Plans shall govern. Where a specifically prepared Technical Specifications section is not in agreement with City Standards Technical Specifications, the specifically prepared section shall govern.

The Contractor shall furnish all labor, equipment, and materials to construct the Project and all miscellaneous and appurtenant work complete in place as specifically described and included under each Contract Pay Item as shown, specified, or directed by the Project Manager in accordance with the obvious or expressed intent of the Contract. The list of drawings comprising this project is included in the bid process.

1.04 INSPECTION AUTHORITY

The Project Manager has ultimate responsibility for Contract administration and inspection for this Project. The Project Manager may assign field inspection responsibilities to a Design Professional and/or City Inspector.

Each step of construction is subject to approval by the Project Manager prior to proceeding with a subsequent step in accordance with the General Conditions article headed "Tests and Inspections" and as supplemented herein.

During the progress of the Work and up to the date of final acceptance, the Contractor shall at all times afford representatives of the City, the County, the State, the Department of Environmental Protection, the Department of Labor, or any other agency with jurisdiction, a reasonable, safe, and proper facility for observation of the Work done or being done at the site and also of the manufacture or preparation of materials and equipment at the place of such manufacture or preparation.

1.05 PROJECT SCHEDULE

The Contractor shall submit a Project schedule in accordance with General Conditions articles headed "Project Schedule" and "Progress Charts" and as supplemented herein.

Scheduling and progress reporting shall be accomplished by the use of a bar chart to provide a clear and concise comparison of progress.

1.06 PROJECT START TIME

A. Contract Time will begin on the 1st calendar day after issuance of the Notice to Proceed or on the actual day that the Contractor commences Work at the site, whichever is the earlier. Extension of Contract Time shall be requested in the manner set forth in the General Conditions article headed "Changes in the Work," subsection headed "Changes in Contract Time," and shall include:

1. Manufacturer's signed affidavit stating reason for delay and lead time required.

2. Number of calendar days requested.

3. Reasons Contract Time must be extended.

4. Stipulation of all Work, including Schedule, which is to be performed during the grace period.

5. List of what insurance and bonds will be active.

B. Documentation shall be presented to the City prior to, or during, the Preconstruction Conference.

C. It may be possible that certain Work items can be accomplished by the Contractor prior to receipt of the custom equipment or materials if, in the opinion of the Engineer, City use of the facility is not impacted.

D. Failure of the Contractor to substantively obtain the custom equipment or materials, if through no fault of the City, will not be justification for extending the Contract Time extension beyond the above maximum duration.

1.07 STORM PREPAREDNESS PLAN

Within 15 days of the date of Notice to Proceed, the Contractor shall file with the Engineer a Storm Preparedness Plan. The plan shall outline the necessary measures the Contractor proposes to perform at no additional cost to the City upon the issuance of an official storm warning issued by the National Weather Service.

In the event of inclement weather, or at the Project Manager's direction, the Contractor shall carefully protect the Work, private property affected by the Work, and stored materials against damage or injury from the weather. If, in the opinion of Project Manager, any portion of the Work or materials is damaged or injured by reason of failure on the part of the Contractor to protect the Work, such Work and materials shall be removed and replaced at the Contractor's expense.

1.08 MATERIALS AND EQUIPMENT

All materials, appurtenances, and types of construction shall be in accordance with the Technical Specifications and shall in no event be less than that necessary to conform to the requirements of all applicable laws and regulations.

All materials and equipment to be incorporated into the Work shall be new, unused, and correctly designed. They shall be of standard first grade quality, produced by expert workmen, and be intended for the use for which they are offered. Materials or equipment which, in the opinion of the Project Manager, are inferior or of a lower grade than indicated, specified, or required, will not be accepted.

Only "Asbestos-Free" materials shall be incorporated into the Work, unless the Technical Specifications specifically call for otherwise. Material suspected of being Regulated Asbestos Containing Material (RACM, includes but is not limited to: thermal and acoustic insulation, joint compound, mastic, adhesive, vinyl floor tile and sheeting, ceiling tile, plaster, wall board, roofing felt, and shingle. Shop drawings for material or equipment suspected of being RACM shall list all contents, shall be noted "Asbestos-Free," and shall be screened by the Contractor prior to submittal to confirm that it is "Asbestos-Free." All materials delivered to the Project site shall have been approved through the shop drawing procedure and shall be in their original labeled and unopened containers.

In the event that asbestos-containing material installed by the Contractor is discovered either during construction, following completion of construction, or following acceptance of the Contract Work by the City and closeout of the Contract, it will be the responsibility of the Contractor to pay all costs incurred to remove and replace those materials, including repair or replacement of all adjacent materials which are affected by the abatement process.

1.09 MANUFACTURER

The names of proposed manufacturers, manufacturers' representatives, suppliers, and dealers who are to furnish materials, fixtures, equipment, appurtenances, or other fittings, shall be submitted by the Contractor to the Project Manager for approval in accordance with the General Conditions article headed "Shop Drawings and Submittals" to afford proper investigation and checking. No manufacturer will be approved for any materials, fixtures, equipment, appurtenances, or other fittings to be furnished under this Contract unless the manufacturer is of good reputation and has a plant of ample capacity. The Contractor shall, upon the request of the Project Manager, be required to submit evidence that the manufacturer has manufactured a product similar to the one specified and that the product has been used for a like purpose for a sufficient length of time to demonstrate its satisfactory performance. All transactions with the manufacturer and subcontractors shall be through the Contractor.

Any two or more pieces of material or equipment of the same kind, type, or classification and being used for identical types of service, shall be made by the same manufacturer.

1-4

1.10 MATERIAL AND EQUIPMENT DELIVERY AND STORAGE

In conformance with the General Conditions article headed "Material and Equipment Delivery" the Contractor shall deliver materials in ample quantities to ensure the most speedy and uninterrupted progress of the Work to complete the Work within the allotted time. The Contractor shall also coordinate deliveries in order to avoid delay in, or impediment of, the progress of the Work of any related contractor. The Contractor shall provide space for storage of materials and equipment.

Pipe strung along roads and rights-of-way shall be placed in a manner that will not endanger or restrict pedestrian or vehicular traffic.

1.11 SERVICE OF MANUFACTURER'S REPRESENTATIVE

The Contract amount shall include the cost of furnishing a competent and experienced representative of the equipment manufacturer who shall assist the Contractor, when required, to install, adjust, test, and place in operation the equipment in conformity with the Contract Documents. After the equipment is placed in operation, the representative shall make all adjustments and tests required by the Plant Maintenance Supervisor to prove that the installed equipment is in proper and satisfactory operating condition. The representative shall instruct personnel designated by the Plant Maintenance Supervisor in the proper operation and maintenance of such equipment.

1.12 SPILL OR DISCHARGE OF WASTEWATER OR RECLAIMED WATER

The discharge of wastewater or effluent (reclaimed water) into waters of the State and/ or into canals, ditches, and ponds that are connected to waters of the State is prohibited. Any spill or discharge of wastewater or reclaimed water shall be immediately reported to the Project Manager, the City’s Wastewater Collection System Manager (727-892-5612), and the City’s Emergency Dispatch Center (727-893-7261). In the event of a spill or discharge, the Contractor shall immediately control, contain, and stop the spill or discharge and shall repair any damage to the City’s facilities. The Contractor shall be responsible for any penalties and costs charged to the City by the FDEP and for all costs incurred by the City as a result of the Contractor’s actions or as a result of the Contractor’s negligence.

1.13 SEQUENCE OF OPERATION

A. General - Plant and Miscellaneous It is essential that any Project Work conducted at Plant sites be sequenced to minimize interference with normal daily operations of the Plant.

The Contractor shall include in the Project Schedule a Sequence of Operations conforming to the following order:

1. Store equipment and materials at locations and in a manner approved by the Maintenance Supervisor.

2. Confine work and personnel to designated areas in accordance with the Specifications.

3. Clean up work areas daily so as to present a safe and neat appearing work site.

4. Required shutdown period for Clarifier #4 improvements.

B. Utility Companies may be present on the Work site adjusting their facilities and installing new facilities. The Contractor's work shall be scheduled in such a manner as to minimize conflicts with various utility companies.

C. The Contractor shall clean up the site for each phase of Work in accordance with the Contract Documents before proceeding to a subsequent phase of Work, unless otherwise approved by the Project Manager.

D. No Time Extension If the Project Manager orders construction, or a phase of construction, to be stopped due to the Contractor's failure to adhere to the Sequence of Operations as outlined herein, the Stop Work Order shall not constitute a basis for extension of time.

E. Sequence of Construction Work under the Contract shall be scheduled and performed in such a manner as to result in the least possible disruption to the operation of the existing treatment facilities. Critical events in the sequence of construction are identified below. The outlined sequence of construction doe not include all necessary items necessary to complete the work, but is intended to identify the sequence of critical events necessary to minimize the disruption to the on-going treatment plant process. It shall be understood by the Contractor that the critical events identified are not all inclusive and that additional items of work not shown may be required. The sequence of construction does not attempt to schedule the Contractor’s work.

1) Request full shutdown of Clarifier #4

2) Demo existing clarifier mechanism and associated apparatuses.

3) Clean and rehabilitate existing tank and apply new interior coating.

4) Install new clarifier mechanism and associated apparatuses.

5) Excavation and install of tie-in to existing waste activated sludge (WAS) line, grinder control panel and electrical.

6) Request permission from City to place system in operation.

7) Restore site in accordance with the Specifications.

1.14 FIELD OFFICE AND APPURTENANT STRUCTURES

General: All structures for use by the Contractor shall be temporary. Permanent facilities shall not be used for field offices or for storage. Structures may be new or used, but must be serviceable, adequate for the required purpose, and shall be in compliance with all applicable codes or regulations.

All security requirements for such facilities shall be provided and maintained by the Contractor.

Before the Final Payment will be paid, and as directed by the Project Manager, the Contractor shall clean up the area, remove any temporary facilities, finish grade, and restore the area to its original condition as determined by the Plant Maintenance Supervisor.

Contractor's Field Office: A field office and work sheds required by the Contractor shall be furnished, installed, and maintained during the entire construction period by the Contractor at his own expense and no separate payment will be made therefore.

Space on City property or rights-of-way proposed to be used for storage and as a field office for the Contractor shall be approved by the Project Manager prior to installation, providing such uses will not interfere in any manner with the construction of the Work or the operation of existing facilities.

1.15 CONTRACTOR'S SIGN

No sign by the Contractor, any subcontractor, or any material supplier, will be allowed on the Project site.

1.16 MOBILIZATION

Mobilization shall include all preparatory work and operations necessary to begin the Project, including moving of personnel, equipment, plant, and all else necessary to commence work. The cost of bonds, insurance, shop drawings, and pre-construction expenses shall also be included.

If a separate Pay Item is included for mobilization, payment will be as specified for that Pay Item. If no Pay Item is included, costs for mobilization shall be included with the costs for the major Work items included in the Proposal.

1.17 WATER PURCHASE

Water used in connection with this Project may be purchased from the Water Resources Department, 1650 Third Avenue North, St. Petersburg, Florida, in accordance with the provisions of applicable ordinances, procedures, and regulations.

1.18 UTILITIES

Prior to construction, the Contractor shall familiarize himself with the location of all existing utilities and facilities within the Project Site and with the applicable provisions of the General Conditions article headed "Public Convenience and Safety."

The Contractor shall notify utility companies at least 48 hours, excluding Saturdays, Sundays, and legal holidays, prior to excavation. Utility companies shall be contacted by calling the utility notification center "Sunshine" at 1-800-432-4770. The City will furnish to the Contractor the available records of City utilities. The Contractor shall locate and mark all City utilities for his reference and for use by utility companies. The Contractor shall act as the City’s agent for locating and marking City underground utilities within the Project limits, in accordance with the Florida Underground Facilities Damage Prevention and Safety Act (FS 556).

In all cases where existing utility lines may be interfered with by the Work, the Contractor shall give a minimum of 48 hours' notice to the owners of such utilities to permit them to relocate the lines prior to construction. Existing utilities have been shown on the Plans insofar as information is reasonably available. However, it will be the Contractor's responsibility to preserve all existing utilities whether shown on the Plans or not.

1.19 SHOP, FIELD AND LABORATORY TESTING

The Project Manager may require testing by certified personnel of certain materials to be incorporated in the Work, such as: soils density, pavement, concrete pipe and appurtenances, and welds. In the event any such testing is required by the Project Manager, a detailed description will be found in these Technical Specifications concerned with the specific item of Work. Where reference is made in the DOT-SSRBC for design mixes, tests of materials, or work performed, or where in the opinion of the Project Manager, tests are required to ascertain compliance with the Specifications, the Contractor shall have such tests made by an approved testing laboratory. No additional payment will be made for these tests.

1.20 SPECIAL CONSIDERATIONS FOR PLANT WORK

A. Staging Area The Contractor's use of plant property for storage of materials, parking of trailers, employee parking, and other uses, shall be as shown on the Plans. If no area is designated, the Contractor shall submit a staging plan to the Plant Maintenance Supervisor for approval prior to mobilizing to the site. The Plant Maintenance Supervisor and the Plant Chief Operator will jointly approve this plan.

Contractors shall restrict operations to approved staging areas and parking areas. Use of unpaved areas for roadways and parking shall not be permitted unless approved by the Plant Maintenance Supervisor.

On-site, temporary fuel storage will not be allowed unless the method of storage is pre- approved in writing by the Project Manager. All fuel storage shall be properly contained to prevent accidental spills from leaking into the surrounding environment.

B. Utilities The Contractor shall provide telephone and sanitary facilities for his employees. Upon written approval of the Project Manager, the Contractor may connect to existing plant electrical and water outlets, if not in use by the City, and if use of these utilities does not affect operation of the plant.

C. Employee Dress and Appearance All Contractors, subcontractors, sales representatives, and their employees, shall be appropriately dressed. All workers and employees working at the plant shall wear shoes, pants, and shirts.

D. Unloading and Delivery of Materials and Equipment The Contractor shall have adequate staff and equipment at the site to receive materials and equipment. City employees and City equipment shall not be used to assist the Contractor in receiving deliveries unless authorized by the Plant Maintenance Supervisor.

E. Use of City Facilities The Contractor shall not use City telephones, restrooms, break rooms, or other facilities provided for City employees' comfort. The Contractor shall not use the City's mailing address to receive mail. The City will not accept mail for the Contractor addressed to City offices or mail box.

F. Clean UP Any waste or extra materials (including sandblast, rubble, brush, dirt, trash, sludge, packing crates, boxes, etc., or equipment and materials replaced, will be the Contractor's responsibility for proper disposal. Disposal on-site or use of City dumpster may be allowed upon Contractor written request and upon receipt of written permission from the Plant Maintenance Supervisor.

The Contractor shall do a thorough cleanup of the construction area daily.

All wire scraps, pipes, fittings, paper scraps, boxes, paint cans, scrap metal, and other scraps, shall be cleaned up daily. Metal scrap may be placed in the City's scrap metal dumpster located at the plant.

If the work is in an area of existing plant structures, the floors shall be swept clean and equipment that was soiled by the construction shall be dusted, on a daily basis.

Any damage to the existing plant facility, equipment, grass, landscaping, pavement, or surrounding structures, shall be restored to as good as or better condition by the Contractor as soon as the Contractor has completed work in the area of the damage, or as directed in writing by the Project Manager.

G. Painting

1. All exposed interior and exterior pipes, conduits, and equipment shall be painted to protect the metal. The number of coats, mil thickness, etc., shall be as specified in the Technical Specifications or Plans or as directed by the assigned paint representative.

2. Unless otherwise specified, finished coating on new or reconstructed Work shall be painted to match the existing color coding. The existing color coding may be obtained from the Project Manager upon request.

3. No lead base paint, including primer, may be used. All paint systems shall have low Volatile Organic Compounds (VOCs).

4. All coatings that come in contact with drinking water shall comply with Florida Administrative Codes and be approved by the United States Environmental Protection Agency (EPA), the NSF International, the Underwriters Laboratories Inc. (UL), or other FDEP/EPA approving agency. This approval must be in writing and a copy of the approval shall be submitted with the shop drawings.

5. Voids between beams, walls, tanks, slabs, and other steel or iron surfaces which would prohibit coating for rust protection must be sealed using an approved sealant.

H. Miscellaneous

1. The Contractor shall not assume that existing valves can be closed and drip-proof. After closing valves, the Contractor shall conduct adequate tests to determine the leakage of the valve and shall submit a procedure to the Project Manager for handling this leakage during the shutdown period.

2. Unless otherwise specified, the Contractor shall restrict his scheduled hours of work to the period 7:00 a.m. to 4:00 p.m. weekdays. Work required to be performed during other periods of time should be shown on the Project Schedule. Emergency work required to be performed after hours shall be subject to approval by the Project Manager.

3. Coordination of the Contractor's work that requires special procedures of the plant operating personnel shall be shown on the Project Schedule and shall be reconfirmed with the Project Manager 48 hours prior to the required special procedure. The Project Manager reserves the right to deny or reschedule work, if such action is needed due to operating demands, personnel availability, or other factors that will impact the City's use of the facility. The Project Manager may grant a time extension to the Contract period if rescheduling impacts the completion time.

1.21 PLANT SECURITY

A. The City’s Water Resources Department conducts background checks of all workers at their treatment facilities. Before coming on site to work, the Contractor shall provide a list of the following:

1. Full names of the employees assigned to be on-site.

2. Social Security Number of each employee. Contractor shall inform all employees of the reason for providing social security numbers to the City in accordance with all applicable laws, rules, and regulations.

3. Birth Date of each employee.

B. The Water Resources Department project coordinator or designated representative will conduct a background check prior to allowing a worker on site. In order to allow time to conduct the background check, the Contractor shall supply this information at least 72 hours in advance of the worker coming to the site. Persons who meet one or more of the following criteria will fail the City's background check and will not be granted access to the City’s wastewater treatment facilities:

1. Listed on the FBI’s list of suspected terrorists.

2. Have an outstanding arrest warrant against them.

3. Convicted of a First or Second Degree felony.

4. Considered a habitual felony offender (after their 18th birthday convicted of two or more felony or 1st degree misdemeanors offenses within any 5-year period).

C. The Contractor will be notified as to who passed the background check and will be allowed on site and who did not pass the background check and will not be allowed on site.

D. Contractors using “day laborers” shall provide the same information as above and with as much notice as possible. If the required information is given less than 72 hours in advance, the City will make its best effort to conduct these background checks in a timely manner. However, because of City staff’s other priorities, website problems, and/or computer problems, it may not be possible to complete the background checks in a timely manner. A worker arriving at the plant site who has not had a successful background check will have to wait outside the plant gate. Workers will not be permitted on site until they have passed the background check.

1.22 SALVAGED MATERIALS

The Contractor shall not proceed with demolition of existing materials or equipment without prior written approval from the Project Manager for the method of disposal.

1.23 PAYMENT TERMS

· Payment will be made in three stages:

10% upon mobilization and approval of submittals.

60% based on progress and verified completion of work components.

30% upon final completion, acceptance by the Project Manager, and receipt of all closeout documents

All payment requests must be accompanied by progress documentation and approved by the Project Manager.

1.24 CONTINGENCY ALLOWANCE

A contingency allowance of $15,000 is included in the Bid Proposal Form for potential unforeseen structural or surface repair work, such as hidden concrete degradation or coating failures discovered during rehabilitation process.

This amount shall be carried as a separate line item in the Bid Schedule.

Use of the allowance shall be at the sole discretion of the Project Manager, and all work must be authorized through a written change directive.

Bidders shall include this allowance in their total bid amount. Any unused portion will be credited back to the City at the conclusion of the project.

SECTION 2 - EXCAVATION AND BACKFILL

2.01 GENERAL

The Work in this section includes furnishing all labor, materials, tools, and equipment for excavation and backfill of roadways, sidewalks, curbs, driveways, pipelines, and structures. The Work also includes removing and disposing of leftover material, and furnishing and placing off-site fill.

Bidders shall examine the site of the Work, make their own additional soil borings and tests, and make their own determination of the character of materials and the conditions to be encountered on the Work; their Proposal shall be based upon their own investigation.

Standards referenced in this section are the latest revision of the following specifications:

AASHTO T 99

"Method of Test for Moisture-Density Relations of Soils Using a 2.5-Kg (5.5-lb) Rammer and a 305-mm (12-14) Drop”

AASHTO T 180

“Method of Test for Moisture-Density Relations of Soils Using a 4.54-Kg (10-lb) Rammer and a 457-mm (18-in) Drop”

ASTM C 33

“Specification for Concrete Aggregates”

ASTM D 1557

“Test Method for Laboratory Compaction Characteristics of Soil Using Modified Effort”

DOT-SSRBC Section 110

“Clearing and Grubbing”

DOT-SSRBC Section 120

“Excavation and Embankment”

DOT-SSRBC Section 901

“Coarse Aggregate”

DOT-SSRBC Section 902

“Fine Aggregate”

DOT-SSRBC Section 921

“Portland Cement and Blended Cement”

DOT-SSRBC Section 923

“Water for Concrete”

DOT-SSRBC Section 929

“Fly Ash, Slag, Microsilica and Other Pozzolanic Materials for Portland Cement Concrete”

FS 90-96

Florida Trench Safety Act Statute

29 C.R.R., S. 1929.650 Subpart P OSHA Trench Excavation Safety Standard

2.02 TRENCH SAFETY

The Contractor shall be responsible for maintaining safety at each excavation. The Contractor shall adhere to the Florida Trench Safety Act (FS 90-96), OSHA trench excavation safety standards (29 CFR, Subpart P, 1926.650), and OSHA trench excavation shielding, sloping, or sheeting requirements. Inspections required by OSHA trench excavation safety standards shall be provided by the Contractor's "competent person," as defined by OSHA 29 CF, Subpart P, 1926. The Contractor's "competent person" shall be identified at the Project preconstruction meeting.

The Contractor certifies by submitting the bid and subsequently executing this Contract, that all trench excavation done within his control shall be accomplished in strict adherence with OSHA trench safety standards, the Florida Trench Safety Act, and public safety.

The Contractor also agrees to produce or obtain, prior to award of the subcontracts, identical certification from subcontractors who will perform trench excavation, and to retain such certification for at least three years following Final Acceptance.

The Contractor shall consider all available geotechnical information when designing the trench excavation safety system. If sufficient geotechnical information is not available, the Contractor may obtain such to support the requirements set forth above, at no additional cost to the City.

2.03 WORK IN WETLANDS, MANGROVES AND PRESERVATION AREAS

Strict adherence to all permits is required. Damage to wetlands, periodically wet areas, mangroves, and preservation areas is prohibited. Any such damage by the Contractor shall be duly rectified at no additional cost to the City and as approved by the regulatory agencies.

2.04 CLEARING AND GRUBBING

All clearing and grubbing Work shall conform to all applicable requirements of DOT-SSRBC Section 110 "Clearing and Grubbing" except as modified herein.

The Contractor shall remove only those trees and bushes necessary to complete the specified Work. Not all the trees and bushes have been located or shown on the Plans. The Contractor shall flag those trees and bushes to be removed. All other trees and bushes shall be protected as specified in Technical Specifications section headed "General," subsection headed "Tree Protection."

All roots, stumps and other debris shall be removed to a depth not less than 12 inches below a bearing surface. The disturbed surface shall be backfilled, graded, and compacted as specified.

No tree or bush shall be removed without the approval of the Engineer. The Contractor shall obtain all necessary City or County permits for each tree to be removed. Tree removal shall conform to the provisions of the Technical Specifications section headed "General," subsection headed "Tree Removal and Replacement."

2.05 ROADWAY EXCAVATION

The extent of excavation shall be as shown on the Plans or otherwise approved by the City, and shall include roadway excavation and/or filling and grading, together with the removal of trees, bushes, existing asphalt, concrete, or other material, as required to facilitate construction and restoration as directed by the City.

All excavation Work shall conform to all applicable requirements of DOT-SSRBC Section 120 except as modified herein.

2.06 TRENCH EXCAVATION

Mechanical excavation shall be terminated at least 2 inches above the proposed pipe bed and trench bottom, then shaped and compacted so as to provide uniform bearing on the barrel of the pipe. Particular care shall be taken to recess the bottom of the trench at the bell of the pipe to relieve the bell of all load.

A minimum trench width shall be maintained, allowing room for the jointing and proper compaction of the backfill. If material is encountered that is unsuitable in the opinion of the Engineer, it shall be removed by the Contractor and replaced with acceptable material compacted in place as specified. In the event the Contractor excavates below the elevation required without approval, the Contractor shall backfill with approved materials compacted to obtain a suitable trench bottom, all to the satisfaction of the Engineer and at no additional cost to the City.

The amount of open trench shall be limited so that no more than 100 feet of open trench in advance of the backfilling operation will remain at the end of that working day. All open trench shall be protected by the Contractor with barriers, warning devices, and traffic control devices, which shall be kept in the correct position, properly directed, anchored when required, and clearly visible at all times. The barriers, warning devices, and traffic control devices shall be suitably lighted at all times when vehicular traffic lights are required.

2.07 STRUCTURE EXCAVATION

Excavation shall be of the size and depth required for construction of structures and their foundations. Unsuitable material encountered shall be removed to the depth required to obtain sound foundation material or as ordered by the Engineer. Over-excavated areas shall be filled with approved backfill material compacted as specified, at no additional cost to the City.

Unsuitable existing soil shall be removed and replaced with compacted material, as approved by the Engineer and as specified in the subsection herein headed "Excavation of Unsuitable Material."

2.08 EXCAVATION OF UNSUITABLE MATERIAL

Unsuitable material shall include rock, concrete, and boulders. Unsuitable soft material shall include logs, muck, other soft soils, organic soils, and other soils as specified or as ordered by the Engineer to be unsuitable.

All excavation of unsuitable material shall conform to all applicable requirements of DOT-SSRBC Section 120 except as modified herein.

Unsuitable material encountered below or within the roadway stabilized subgrade, the trench bottom, or a structure bottom, shall be removed by the Contractor to the limits established by the Engineer and disposed of from the Work area at an approved disposal area. Unsuitable material shall be replaced with approved material and compacted as specified.

No additional payment will be made for backfill material obtained from any source and used to replace any unsuitable material except as otherwise specified. Limerock shall not be used as backfill material.

2.09 SHEETING, SHIELDING AND SLOPING

All excavations shall be properly sheeted, shielded, or sloped to the required slope to furnish safe working conditions, to prevent shifting of material, to prevent damage to structures or other Work, and to avoid delay to the Work, all in accordance with applicable safety and health regulations. The minimum sheeting and shielding for trench excavations shall meet the general trenching requirements of the Florida Trench Safety Act and OSHA standards.

The sheeting and shielding shall be of adequate strength and quantity for the purpose intended. Any sheeting extending below the level of above the top of pipeline shall be cut off as ordered by the Engineer and left in place. In addition, the Engineer may order the Contractor to cut off and leave in place any sheeting, shielding, or other approved support where required to protect construction, property, or existing facilities or utilities.

Damages resulting in the installation or removal of sheet piling shall be rectified by the Contractor at no additional cost to the City.

2.10 DEWATERING

All pipeline and appurtenances shall be laid entirely in a dry trench. All foundations and structure walls shall be constructed or installed in a dry excavation.

Before commencing any excavation at the site of the Work, the Contractor shall submit to the Engineer for review, the methods, equipment, and arrangement of facilities proposed for dewatering and disposal of water at the site and of all water entering any excavation or other part of the Work from any source whatsoever.

Water discharged from dewatering equipment shall be carried into surface drainage facilities, except water quality treatment systems, and shall not be discharged into sanitary sewer lines. The Contractor shall prevent water from puddling in streets or on private properties. The depositing of dirt in storm drains or ditches, and the staining of existing facilities, are not allowed.

Adequate standby facilities shall be provided to ensure that the excavation will be kept dry in the event of power failure or mechanical breakdown. Facilities for the removal and disposal of water shall be of sufficient capacity to keep the excavation dry under all circumstances with one-half of the facilities out of service. If well points are used, provision shall be made for removing and resetting individual well points without taking the system of which they are a part out of service.

The City reserves the right to require the Contractor to replace noisy equipment in order to keep disturbance to a minimum.

The cost of dewatering and disposal of water shall be included in the unit quantity for each appropriate item bid.

Refer to the Technical Specifications Section headed "General," subsection headed "Contaminants Containment/Disposition," for requirements concerning encountered groundwater contaminates.

2.11 BORROW MATERIAL

Any borrow excavation Work shall consist of the excavation and satisfactory utilization of material from areas provided by the Contractor when necessary material is not available from the normal excavation or grading operations. This Work shall conform to DOT-SSRBC Section 120 except as modified herein.

If additional fill material is required, it shall be City approved material supplied and compacted by the Contractor. All compaction under roadway, alley, driveway, curb, walk, or other improved surface shall be to a density as specified. Unless otherwise directed by the City, all material not required for construction shall be removed from the premises and disposed of by the Contractor.

2.12 BEDDING MATERIAL

Where shown, ordered, or required, the Contractor shall place bedding material prior to placing pipelines, structures, or slabs. Bedding material may be either excavated approved native sand, concrete sand, gravel, or reclaimed concrete. Limerock is not allowed.

Off-site bedding material shall be sand or gravel. Sand bedding material shall be a clean concrete sand of uniform gradation between sieve sizes No. 4 and No. 50. All particles shall pass a 3/8-inch sieve and no particles shall pass a No. 100 sieve.

Gravel bedding material shall meet the requirements of ASTM C33 and shall be coarse aggregate, DOT Size No. 67 (3/4-inch to No. 4) or approved equal.

Reclaimed concrete bedding material shall be graded to meet the size requirements as specified for gravel bedding.

Bedding material, where required, shall be placed in lifts and compacted in a manner to achieve the specified density as described elsewhere.

If gravel or reclaimed concrete bedding is used, an impermeable groundwater barrier shall be placed at 100-foot intervals.

The impermeable groundwater barrier shall consist of a 10 mil sheet of polyethylene covering the full cross sectional area of the gravel, embedded 6 inches into the trench sides and bottom, and extending to the top of the bedding. The barrier shall be offset a minimum of 2 feet from any culvert or pipe joint. Ends and splice points shall be lapped a minimum of 12 inches.

2.13 STRUCTURAL SLAB BEDDING

Structural slabs for manhole bases, footings, and similar structures shall be placed on approved compacted bedding material and leveled as specified and/or as shown.

2.14 BACKFILL COMPACTION

All backfill shall be compacted as specified herein and shall meet the following minimum density as determined by the AASHTO T-180 method for backfill outside the rights-of-way and in City streets, and by the AASHTO T-99 method if in County or State rights-of-way.

AASHTO T-180 Method C or D will be used for stabilized subgrade and base compaction tests, and Method A or B will be used for backfill testing, or as directed by the Engineer or jurisdiction.

*Roadway stabilized subgrade and base material shall meet LBR requirements as specified in the Technical Specifications section headed "Roadway Construction," subsections headed “Stabilized Subgrade” and “Roadway Base."

Moisture content of backfill material shall be controlled in order that compaction occurs when the material is within +/- 2 percent of optimum as developed by the Modified Proctor moisture-density relationship set forth in ASTM D-1557. To control the moisture content, the Contractor shall mechanically rework or aerate the backfill material as necessary prior to compaction.

2.15 BACKFILLING OF TRENCH

Backfilling shall be accomplished with suitable material, and shall commence only after the pipelines have been laid and tentatively accepted by the City. The space between the pipe and the sides of the trench shall be packed full by hand-shoveled earth free from lumps or debris.

The backfill material shall be placed in 6-inch lifts and compacted, using approved tampers to the required compaction, to a point 12 inches over the top of the pipe. The remaining backfill (under areas other than roadways) shall be placed in uniform lifts not greater than 12 inches thick (or less as approved for mechanical equipment available) and tamped to the required compaction. Backfill under roadways shall be compacted in 6-inch lifts.

2.16 BACKFILLING STRUCTURES

Backfill around structures shall be of suitable job-excavated material, suitable off-site fill material, or other material approved by the Engineer. Such backfill shall extend from the bottom of the excavation or top of bedding to the bottom of pavement base course, the bottom of lawns or lawn replacement, the top of the existing ground surface, or to such other grades as may be shown or required.

The backfill shall be placed in uniform lifts not greater than 12 inches thick, and thoroughly compacted in place.

2.17 BACKFILLING UNDER ROADWAYS

Backfill placed under roadways and other paved surfaces shall be compacted in 6-inch lifts and thoroughly compacted in place, with suitable equipment as specified herein.

2.18 DISPOSING OF LEFTOVER MATERIAL

The Contractor shall bring the surface to the same level as existed prior to the excavation. All leftover material shall be hauled from the site and disposed of by the Contractor. Leftover material shall not be stored in or along rights-of-way or easements.

2.19 ADJACENT FACILITIES

The Contractor shall be responsible for the protection, removal, and replacement of all adjacent structures, utilities, trees, shrubbery, curbs, culverts, headwalls, fences, City-maintained signs, and other miscellaneous City-maintained structures encountered during the course of the Work.

2.20 TEMPORARY SUPPORTS

Temporary supports for 16-inch and larger pressure and gravity pipes shall be designed by the Contractor and submitted to the City as required by the Contract Standards: General Conditions section headed "Shop Drawings and Submittals." Temporary supports that include a structural beam, or other such member(s), shall be designed, signed and sealed by a Professional Engineer.

2.21 FLOWABLE FILL

Where shown on the Plans, or where ordered by the Engineer, the Contractor shall backfill a void area or an excavation with flowable fill. Flowable fill may be shown, or ordered, to fill abandoned pipes, abandoned underground steel storage tanks, trench backfill, washout area under structural slabs or behind walls, or other similar locations.

Flowable fill shall be produced and delivered to the site. Placing of flowable fill shall be by chute, pumping, or other approved methods. Flowable fill shall be placed to the designated fill line without vibration. The Contractor shall take all necessary precautions to prevent any damage caused by hydraulic pressure of the fill during placement prior to hardening. Flowable fill shall not be used for pipe bedding and backfill in the zone from the bottom of a pipe to 12 inches above the top of pipe.

Flowable fill shall consist of materials conforming to DOT-SSRBC Sections as follows:

The Contractor shall submit a proposed flowable fill design mix that will produce a flowable fill meeting the strength requirements specified herein, using the following materials:

Pounds per cubic yard

Note: 6-inch to 10-inch slump

Flowable fill material shall be proportioned to produce a 28-day compressive strength approximately as follows:

Pounds per square inch

Note: Density in place 115 to 145 pounds per cubic foot.

Not more than 60 minutes shall elapse between the start of moist mixing and the placement of the flowable fill.

Flowable fill placed on slopes shall have a reduced slump with a reduction in water, and shall be able to be shaped as required.

The Contractor shall place the flowable fill in such a manner as to eliminate all cavities.

Flowable fill shall not be placed in salt water. When within a tidal area, the flowable fill shall be placed immediately after the salt water has receded.

When flowable fill is used adjacent to ductile iron pipe, the pipe shall be polyethylene encased.

SECTION 3 - PIPING MATERIALS: DUCTILE IRON PIPE

3.01 GENERAL

The Work in this section includes furnishing all ductile iron pipe, fittings, joints, and appurtenant materials. All castings furnished shall have been cast in the United States of America unless complete certification is furnished in accordance with the latest edition of ANSI/AWWA C 110.

Standards referenced in this section are the latest revision of the following specifications:

ANSI/AWWA C104

"Cement Mortar Lining for Ductile-Iron Pipe and Fittings for Water"

ANSI/AWWA C110

"Ductile-Iron and Gray Iron Fittings, 3-Inch through 48-Inch, for Water and Other Liquids"

ANSI/AWWA C111

"Rubber Gasket Joints for Ductile-Iron and Pressure Pipe and Fittings"

ANSI/AWWA C115

"Flanged Ductile Iron Pipe with Threaded Flanges"

ANSI/AWWA C150

"Thickness Design of Ductile-Iron Pipe"

ANSI/AWWA C151

"Ductile-Iron Pipe, Centrifugally Cast, for Water or Other Liquids"

ANSI/AWWA C153

"Ductile-Iron Compact Fittings, 3-Inch through 24-Inch, for Water and Other Liquids"

3.02 PIPE

A. General

All ductile iron pipe shall be designed in accordance with ANSI/AWWA C150. Pipe shall be minimum pressure class as follows:

For threaded…