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Exhibit 3Denton Municipal Electric

City of Denton, Texas

TECHNICAL SPECIFICATIONCONSTRUCTION OF HICKORY SUB UNDERGROUND

TRANSMISSION LINE DUCT BANKRFP# 6416

I. SPECIAL CONTRACT REQUIREMENTS AND PRICE ITEM DEFINITIONS

A. Special Contract Requirements

1. The October 2004 edition of the North Central Texas Council of Governments Standard Specifications for Public works Construction will be utilized as a basis for both general and technical procedures to include types of materials and construction procedures used in the City of Denton. The following specifications and definitions are intended to (1) highlight requirements in the NCTCOG found on most projects in the City of Denton, (2) make specific requirements for materials or procedures where the NCTCOG gives options, (3) specify provisions for deviation from the NCTCOG, and (4) define the pricing items listed in Exhibit 1 Pricing Sheet. The following specifications are also numbered in accordance with the NCTCOG to aid in locating more specific requirements. In addition to this section of the technical specifications, section II Special Contract Requirements for Duct Banks also provide technical specifications to be utilized for the project.

Conflicts sometimes arise when City of Denton provisions conflict with either the plans for the project or the North Central Texas Council of Governments specifications. The following order of precedence shall generally be followed in case of conflicts; however, the City Engineer shall make the final determination:

1. City of Denton construction plans2. City of Denton project specifications3. NCTCOG Standard Specifications

2. Manufacture Information

The Contractor shall submit five (5) copies of information to the City from all manufacturers for materials and equipment to be used on the project. This information shall include:

(A) Product specifications sufficient to allow the City to determine whether the materials and equipment conform to the design concepts and project specifications.

RFP 6416 – Exhibit 3 TS-1

(B) Information on all warranties provided by the manufacturer.

All submittals shall be stamped by the manufacturer indicating that the manufacturer has checked the submittal for compliance with the specifications. Unstamped or certified submittals shall be returned to the manufacturer unprocessed.

Submittals shall be provided to the City prior to or at the preconstruction meeting. Construction will not be allowed to proceed until all submittals have been approved or a written waiver is given by the City.

3. Conflicts in Documentation

In the event that conflicts are discovered between this Technical Specification and the RFP instructions, the more restrictive statements shall apply.

4. Complete And Functional Construction with New Material

It is the intent of this specification to require duct bank improvement work that provide new complete and functional systems. RFP pricing shall reflect this requirement. It is not possible to specify or describe every detail of work required to complete a project of this nature or to predict problems that might be encountered. The successful Contractor will be required to provide all labor, equipment, tools, specified material, and incidental items necessary to undertake the construction and complete the project, as described herein, resulting in fully prepared and functional systems that perform to their intended purposes. Minor omissions from the specification or drawings shall not relieve the Contractor from the obligation to provide the completed project that is fully functional as intended by the City. Failure of this specification to describe each detail or incidental item necessary for a complete and functional project shall not entitle the Contractor to additional charges. Examples of items that will not be considered as basis for claims for additional cost are, but shall not be limited to, minor relocations, minor changes in the grade, differences in the actual surface of the site from that shown on the drawings, reasonable weather delays, site cleanup, etc. Further, all work shall be performed and completed in a thorough and workmanlike manner and shall follow the best modern recognized practices, notwithstanding any omissions from this specification.


5. Price Calculation for Evaluation

The price to be used in evaluating the RFPs will be constructed by applying the unit price to the quantities shown on the RFP pricing sheet to arrive at a total price for the project.

B. Price Items

Payment sections of the specifications include all material, labor, and equipment necessary to complete the project.

General:

Item 103.3 Mobilization / Demobilization

General: This item includes mobilization cost such as site equipment and personal mobilization, up front coordination and other activities to prepare for the start of work. This item also governs the demobilization for the project including record drawings, general site final clean up, equipment and personal departure from the site, and other project closing activities.

NCTCOG Reference: Item 103.3, 107.24, 107.25, 107.26

Payment: Payment shall be at the contract lump sum price for Mobilization/ Demobilization.The combination of mobilization/demobilization will be paid once only at the initial time equipment and personnel are brought to the site. Mobilization will not be paid for replacements of equipment whether due to maintenance needs or for other reasons. Demobilization will not be paid at the final time equipment and personnel are removed from the site and all required demobilization items are satisfactorily provided. The City will consider additional mobilization cost if work must be halted on the site and work delayed until a significantly later time as long as the halted work and delay is not due to the Contractor’s negligence in performing the work.

Item 103.3 Surety Bonds

General: This item shall be used to separate the bonds as specified in the contract documents into a separate RFP item. Include all bonds with their related costs in this item except for RFP Bond.

NCTCOG Reference: Item 103.3

Payment: Payment shall be lump sum for all bonds provided for in the proposal.


Item 107.25 Disposal of Materials

Vegetative material removed as a result of work operations shall be transported off-site and deposited at a legal site in accordance with all applicable Federal, state, and local laws and regulations. Removed vegetation will not be allowed to remain in piles or mounds on the easement or surrounding property.

NCTCOG Reference: Item 107.25

Payment: No separate payment shall be made for disposal of vegetative materials. The disposal of vegetative materials shall be considered a subsidiary cost of General Site Preparation (Item 203.3)

Item 107.19.3 Trench Safety

General: Excavation protection, where required, shall be in strict compliance with NCTCOG Item 107.19.3 and the most current OSHA regulations. The Contractor shall submit three (3) copies of his site specific trench safety plan prepared by a licensed Professional Engineer in the State of Texas to the City prior to construction. The City will not review the submittal; it is simply a confirmation that the Contractor has prepared a trench safety plan as required by state and Federal law. The City assumes no responsibility for trench safety and shall be held harmless under the indemnification clause of NCTCOG Item 107.19.3.2. Any changes in the trench excavation plan after initiation of construction will not be cause for an extension of time and will require a new submittal to the City. The Contractor accepts sole responsibility for compliance with all applicable safety requirements.

NCTCOG Reference: Item 107.19.3

Payment: Payment for this item shall be at the contract unit price per linear foot of excavation protection measures utilized for the Duct Bank improvements.

Item 201 Temporary Erosion Control

This price item is covered by City of Denton Amendments to NCTCOG Specifications Item 201 Temporary Erosion Control.

Item 202.5 Sod Restoration

This price item is covered by City of Denton Amendments to NCTCOG Specifications Item 202.5 Sodding.

Item 202.6 Hydro-seed Restoration


This price item is covered by City of Denton Amendments to NCTCOG Specifications Item 202.6 Seeding Turf Grass.Item 203.3 General Site Preparation

This price item is covered by City of Denton Amendments to NCTCOG Specifications Item 203.3 General Site Preparation.

Item 801 Traffic Control, Barricades, Barriers, and Warning Signs

This price item is covered by City of Denton Amendments to NCTCOG Specifications Item 801 Barricades, Detours, and Warning Signs.

Duct Bank:

Item D-01 Duct Bank Conduit

General: This item includes the cost of furnishing and installing the conduit system for this project. The conduit system includes eight (8) six inch Schedule 40 PVC conduits, four (4) two inch Schedule 40 PVC conduits, two (2) four inch Schedule 40 PVC conduits, all required conduit spacers and all other material to properly secure the duct bank to the ground. This item also includes all excavation, backfill, shoring and all other construction activities required to open up the trench and provide complete restoration in accordance with all applicable permits and government regulations. Thermal Concrete shall not be included within this item, see Item D-02 Duct Bank Thermal Concrete.

Payment: Payment for this item shall be at the contract unit price for duct bank conduit based on per linear foot of trench measured along the centerline of trench.

Item D-02 Duct Bank Thermal Concrete

General: This item includes furnishing and installing approved thermal concrete as backfill within the trench for the width and depth as shown on the drawings and specified within the technical specifications. Only pre-approved thermal concrete shall be used.

Payment: Payment for this item shall be at the contract unit price for duct bank thermal concrete based on per linear foot of trench measured along the centerline of trench.

Item D-03 Temporary Construction Facilities

General: This item includes the cost of furnishing, installation, and subsequent removal of all temporary construction plant, utilities, temporary facilities, temporary equipment, materials and supplies required for completion of the installation work, but which will not be incorporated in the completed work. This item includes but is not limited to the following items, construction trailers, fencing, security, sanitation, power and water, temporary parking area and access for adjacent apartment complex.


Payment: Payment for this item shall be at the contract lump sum price for Temporary Construction Facilities.

Item D-04 Dewatering

General: This item includes the cost of furnishing and installation of all necessary dewatering equipment to maintain stable trench conditions and the disposal of the water in accordance with all applicable federal, state and local regulations.

Payment: Payment for this item shall be at the contract lump sum price for Dewatering.

Item D-05 Concrete Parking Lot and Driveway Restoration

General: This item includes the cost of furnishing and installation of lime stabilization, reinforced concrete paving, reinforced concrete driveways, and reinforced concrete curb and gutter for the concrete parking lot and driveways associated with the duct bank improvements. The improvements shall be in accordance with the City of Denton Standard drawings, NCTCOG specifications and City amendments to the NCTCOG Specifications sections 301, 303 and 305. All necessary equipment, labor, and materials shall be included within this item to complete the improvements.

Payment: Payment for this item shall be at the contract unit price per square yard of concrete parking lot and driveway restoration complete and in place. Linear footage of concrete curb and gutter restoration shall be considered subsidiary to the concrete paving restoration.


II. SPECIAL CONTRACT REQUIREMENTS FOR DUCT BANKS

TABLE OF CONTENTS

SECTION 22010 GENERAL DESCRIPTION AND SCOPE OF THE WORK

Part 1 – General1.01 Scope1.02 Project Description1.03 Definitions

Part 2 – Products2.01 Materials2.02 Miscellaneous Materials and Services

Part 3 – Execution3.01 Work Included Under These Specifications3.02 Lines of Demarcation3.03 Contractor's Services3.04 Contractor's Project Team3.05 Project Management3.06 Coordination3.07 Conformed to Construction Records3.08 Inspections

SECTION 22070 TEMPORARY CONSTRUCTION FACILITIES

Part 1 – General1.01 Scope

Part 2 – Products2.01 Construction Plant and Temporary Facilities2.02 Construction Utilities

Part 3 – Execution (Not Applicable)

SECTION 22080 DUCT SYSTEM

Part 1 – General1.01 Scope

Part 2 – Products2.01 PVC Conduit2.02 Inner Duct2.03 Conduit Storage and Transportation2.04 Mule Tape


Part 3 – Execution3.01 Duct Bank3.02 Conduit Installation3.03 Conduit Solvent-Cemented Joints3.04 Conduit Temperature3.05 Conduit Termination3.06 Inspection

SECTION 22100 CONCRETE

Part 1 – General1.01 Scope1.02 Reference Standards1.03 Quality Assurance

Part 2 – Products2.01 Materials2.02 Concrete Strength and Quality

Part 3 – Execution3.01 Mixing and Placing3.02 Forms3.03 Testing3.04 Submittals3.05 Laboratory Qualifications

SECTION 22140 EARTHWORK

Part 1 – General1.01 Scope1.02 Definitions1.03 Materials Ownership

Part 2 – Products2.01 Warning Tape

Part 3 – Execution3.01 Preparation3.02 Tree Protection3.03 Clearing and Grubbing3.04 Topsoil Stripping3.05 Disposal3.06 Sheeting and Shoring3.07 Over Excavation3.08 Site Preparation3.09 Fills and Embankments3.10 Structure and Trench Subgrades3.11 Structure Backfill3.12 Trench Excavation3.13 Trench Widths3.14 Mechanical Excavation


3.15 Trench Depth3.16 Trench Backfill3.17 Final Grading3.18 Disposal of Materials

SECTION 22175 DEWATERING

Part 1 – General1.01 Scope1.02 Related Documents1.03 References1.04 Definitions

Part 2 – Products2.01 Equipment and Materials

Part 3 – Execution3.01 Performance Requirements3.02 Submittals3.03 Environmental Requirements3.04 Groundwater Control3.05 Requirements for Eductor, Well Points, Deep Wells, or Sock Drains3.06 Excavation Drainage3.07 Maintenance and Observation3.08 Monitoring and Recording3.09 Surface Water Control


SECTION 22010GENERAL DESCRIPTION AND SCOPE OF THE WORK

PART 1 – GENERAL

1.01 SCOPE

A. This section provides a general description, scope of work and supplementary requirements for equipment, materials, and services included under these specifications.

B. The work shall include the furnishing and installation of a complete transmission duct bank system for a 138 kV cable system as shown on the plan drawings. This work shall include but is not limited to providing at a minimum: obtaining applicable local, state and federal construction permits, and installing concrete-encased duct bank per project plan drawings. Contractor is to provide miscellaneous materials and services to complete the installations as specified herein and in accordance with the Owner contract documents. The work scope includes all associated work items and materials required to perform the aforementioned major work items in a first class professional manner.

C. These specifications cover the furnishing and installation of the civil infrastructure required for the 138 kV underground transmission line. The furnishing and installation of the 138 kV cable and accessories is a separate contract.

1.02 PROJECT DESCRIPTION

A. The work under these specifications shall include furnishing and installing a complete and operable duct bank system per supplied drawings both between the new Hickory Street GIS Substation and the stub out locations as indicated.

1.03 DEFINITIONS

A. As used in these Specifications, the following terms have the following meanings:

"Owner," shall mean City of Denton, its successors and/or assigns.

"Manufacturer" or "Contractor" shall mean any individual, firm, company, corporation, etc. providing manufacturing, construction or other services under this contract with City of Denton.

"Engineer" shall mean POWER Engineers, Incorporated or Teague Nall and Perkins, Incorporated.

"Project" shall mean the Hickory Street GIS Project.

"Site(s)" shall mean the lands in or on which work is to be completed, including transmission centerline.



PART 2 – PRODUCTS

2.01 MATERIALS

A. Major components of the work include furnishing the following:

1. Open Cut Excavationa. Vegetation clearingb. Trench excavationc. Sheeting/shoring system (as required)d. Dewatering system (as required)e. Erosion and sediment controlf. 6-inch schedule 40 PVC conduits for 138 kV power cablesg. 4-inch schedule 40 PVC conduits for communication cablesh. 2-inch schedule 40 PVC conduits for ground continuity conductors and temperature

monitoring cablesi. Conduit spacersj. 3000 psi duct bank concrete (thermally approved)k. Red warning tapesl. Backfill (compacted, thermally approved)m. Trench restoration back to original conditions, including pavement restorationn. Applicable local, state and federal construction permits

B. All material to be installed must have written approval by Owner. Materials must be submitted 60 days prior to installation for approval. Any material not accepted by Owner must be re-considered and re-submitted for approval before installation, at Contractor’s expense.

2.02 MISCELLANEOUS MATERIALS AND SERVICES

A. Miscellaneous materials and services not otherwise specifically defined shall be furnished by the Contractor in accordance with the following:

1. All nuts, bolts, gaskets, special fasteners, backing rings, tapes, glue and miscellaneous hardware required to assemble and interconnect components and equipment furnished under these specifications

2. Field office and furnishings for Contractor's field supervisor

3. Necessary Storage Facilities

4. Test lab, to verify thermal requirements of native soil, backfill and concrete. A test lab shall also be used for non-thermal property testing of installed properties for soil and concrete.



PART 3 – EXECUTION

3.01 WORK INCLUDED UNDER THESE SPECIFICATIONS

A. The work under these specifications shall include installing all materials and services required to perform the Civil Construction complete in accordance with the specifications, the drawings, and other Contract Documents, except as specifically excluded herein under “Owner Furnished Equipment and Materials” and “Work Not Included Under These Specifications.”

B. Major components of the work consist of installing the items listed in Part 2.

C. Additional components of the work are as follows.

1. Applicable local, state and federal construction permits

2. Thermal testing of select backfill materials, duct bank concrete, and native soils

3. Trench excavation backfill

4. Verify design surveys (Note: City will provide construction survey)

5. Traffic control, as required

6. Safety training, as required by applicable local, state, federal agencies and Owner

7. All project site preparation required for the project

D. After conduit installation, the system will be proof tested via swab and mandrel by the Contractor, with the Owner present, to demonstrate its acceptance for cable installation (by Others). If the tests indicate that the conduit system fails to meet guaranteed performance, the Contractor shall take action to rectify the installation at no additional cost to the Owner.

E. The Owner will provide a Stormwater Pollution Prevention Plan (SWPPP). The Contractor will be in responsible charge of implementation and maintenance of the SWPPP for the duration of the civil installation. This will include performing the weekly inspection (or more frequent if dictated by rainfall) of sedimentation and erosion control features and filling out the SWPPP Inspection Report Form.

F. The Contractor shall install a silt fence and/or a turbidity barrier as dictated by the SWPPP. For limits of the corridor that do not have a silt fence or turbidity barrier, the Contractor shall install a construction fence to define the limits of the work area. The construction fence is not required at access entry points into the corridor. The Contractor will maintain the silt fence, turbidity barriers and construction fence for the duration of the civil installation.

G. Contractor shall backfill trenches overnight to the fullest extent possible. In cases where trenches cannot be backfilled and must be left open overnight, construction fence or other



safety fencing shall be installed around the entire perimeter of open trenches to prevent pedestrian or animals from entering the open trench. For trenches within the street, trench shall be backfilled to grade or steel plated at the end of the workday.

H. Contractor is responsible to locate and protect all existing utilities within the corridor and maintain adequate clearance during excavation work. Existing utilities information depicted on the Drawings are based on limited information and are not intended to be all inclusive. Contractor shall exercise caution at all utility crossings. No mechanical excavation shall be allowed within two feet of the existing underground utility. Contractor shall completely expose the underground utility by hand excavation.

I. The scope of work includes trench dewatering, as required.

J. The on-site installation work shall be in accordance with the requirements specified herein. The Contractor shall furnish all construction materials, labor, supervision, tools, equipment, and supplies required to perform the installation work from unloading to completing the entire civil installation work.

K. The Contractor shall perform all work in adherence with Owner, city, county, state, federal or other applicable safety requirements. The Contractor is responsible to determine all safety procedures.

L. All Contractors and subcontractors shall comply with and attend any and all Owner-required safety courses and procedures (examples-confined space certification and substation and plant safety requirements).

3.02 LINES OF DEMARCATION

A. The following description identifies the line of demarcation between the various contractors. See drawings for further clarification.

1. Civil Infrastructure Furnish and Install Contractor ( this Contract ) – The civil infrastructure furnish and installation contractor shall be responsible for the installation of the following items, and are included in this Contract:

a. Clearingb. Concrete encased duct bank system, including termination vaultsc. Dewateringd. Stormwater Pollution Prevention Plan Implementation and Maintenancee. Surface Restoration

2. Cable and Accessories Furnish and Install Contractor (not this Contract) – The cable and accessories furnish and installation contractor shall be responsible for the installation of the following items, and are not included in this Contract:

a. 138 kV XLPE insulated transmission cablesb. 138 kV terminations c. Cable clamps and supports for cable installation on termination structuresd. Ground continuity conductorse. Sheath grounding equipment (link boxes, sheath voltage limiters, bonding leads etc.)

and all associated material for a complete single point bonded system



3. By Others (not this Contract) – The installation of the following additional items will be accomplished by others, and are not included in this Contract:

a. Termination structures and associated foundations b. Jumpers from terminations to associated switchesc. Surge Arresters

3.03 CONTRACTOR'S SERVICES

A. Services called for in WORK INCLUDED UNDER THESE SPECIFICATIONS shall be in accordance with the following:

1. Submittal of Engineering Data

a. Drawings and other engineering data for the specified equipment and materials are essential to the design and subsequent construction of the entire project. Time is of the essence in completing each phase of the work so that the facilities can be in commercial operation on the specified date.

b. The Contractor will be required to submit drawings and engineering data in accordance with the schedule and requirements specified herein to assure compliance with the overall construction and operating schedule.

c. The Contractor shall allow a reasonable amount of time for the Engineer's review of drawings and data in his engineering schedule and procurement/production/shipping schedule.

B. The Contractor shall submit for Owner’s and the Engineer’s approval the qualifications of the personnel who will be constructing the new facilities. Work shall not proceed until the Owner and the Engineer have reviewed and provided written approval of the Contractor and Subcontractor qualifications and the qualifications of personnel performing the work on these systems in accordance with this Section.

3.04 CONTRACTOR’S PROJECT TEAM

A. The Contractor shall identify a dedicated project team to perform all technical services, testing, and installation of work related to this Section. The project team shall be responsible to the Contractor's project manager. The Contractor's project manager shall be a single point contact for the Owner, Engineer, and Cable Installer for all work and services provided under this contract, and shall have all resources at his disposal to perform all services and work under this contract on the schedule in Section 22010, Article 3.06.

B. Project team members shall attend design meeting as required, depending on the matters scheduled to be discussed.

3.05 PROJECT MANAGEMENT

A. Contractor project management functions shall include the detail planning, scheduling and reporting of all procurement, construction and testing activities necessary to manage the project in accordance with the schedule and milestones specified in the Contract.



B. The schedule requirements shall include a baseline schedule, current schedule, and three week look-ahead schedule. Updates to the current schedule and three week look ahead schedule shall be weekly.

3.06 COORDINATION

A. The Contractor shall coordinate the work with that of other contractors and shall cooperate fully with the Owner in maintaining orderly progress towards completion of the project as scheduled.

B. The Contractor shall keep himself and its Subcontractors advised at all times during the course of construction regarding delivery status of the Owner furnished equipment and materials, and of the progress of construction work being performed under separate contracts.

C. The Owner will, upon written request by the Contractor, furnish information that may be available to the Owner regarding the status of the Owner furnished equipment and materials or construction work being performed under separate contracts.

3.07 CONFORMED TO CONSTRUCTION RECORDS

A. The Contractor shall be responsible for maintaining accurate construction records documenting the status of the construction process. Red-line as-built drawings shall be kept in the construction office. These drawings shall be available at all times to the Owner for review.

B. The following information shall be provided at a minimum:1. Length of each installed duct bank section; with shots taken at centerline for

bottom of trench and top of duct bank conduit; a maximum of 25’ intervals, and more frequently for all changes of direction and elevation

2. Documentation and drawing associated with in field modifications that were made.

C. Contractor shall provide the final construction records to the Owner prior to Final Acceptance.

3.08 INSPECTION

A. The Owner will have inspectors on site during construction to support the transmission construction inspection and monitoring process. The inspectors will perform comprehensive inspections to assure compliance with the specification requirements. These inspections include, but are not limited to, soil excavation and backfill, thermal testing, and duct proofing.



B. The Contractor will provide manpower and equipment as necessary to support these inspections. The Contractor shall supply weekly schedule updates to the Inspectors in order to assist in planning the inspection activities.

END OF SECTION 22010


SECTION 22070TEMPORARY CONSTRUCTION FACILITIES

PART 1 – GENERAL

1.01 GENERAL

A. This section covers the scope of the on-site field work to be performed, and the construction facilities and services to be provided by the Contractor and the Owner.

B. The Owner will provide space for the Contractor’s facilities. Facilities and security fencing shall be provided by the Contractor.

PART 2 – PRODUCTS

2.01 CONSTRUCTION PLANT AND TEMPORARY FACILITIES

A. The Contractor shall furnish all construction plant, utilities, temporary facilities, equipment, fencing, security, materials and supplies required for completion of the installation work, but which will not be incorporated in the completed work.

B. Prior to installation of any Contractor-furnished temporary facilities on the job site, proposals for such facilities shall be submitted to and written approval received from the Owner.

C. All temporary structures and facilities furnished by the Contractor shall remain the property of the Contractor and shall be maintained throughout the installation work. Any materials, equipment, or temporary structures installed or erected on project site by the Contractor shall be removed by the Contractor when so directed by the Owner to permit the execution of other work in connection with the project and at the completion of the Contractor's work.

D. All Contractor-furnished construction plant and facilities shall be kept in first-class condition and shall be of the proper type and size to perform the work. The plant and facilities shall be regularly and systematically maintained throughout the work to ensure proper and efficient operation, which are inadequate or improperly maintained shall be promptly modified, repaired or removed from the project site and replaced as directed by the Owner, and shall be done so at the Contractor's expense.

E. When the installation work is completed, all Contractor-furnished temporary structures and facilities shall be removed from the project site and the area shall be restored to its original condition to the maximum extent practicable.

F. All construction plant and temporary facilities requiring use of wood shall be constructed of Class A Fire Retardant Pressure Impregnated Wood.

G. Temporary structures for offices and other uses for the Contractor or its Subcontractors shall be provided by the Contractor unless otherwise specified herein. Suitable



construction trailers shall be placed only in the locations assigned by the Owner or negotiated by the Contractor with a third party.

H. Temporary parking for the adjacent apartment complex shall be provided per the design drawings.

I. Chain link construction fence shall be provided for the Contractor’s staging area per the design drawings.

2.02 CONSTRUCTION UTILITIES

A. Construction utilities required for the execution of the work shall be provided by the Contractor, at the Contractor’s sole expense, as herein specified.

1. Telephones and Other Project Site Communication Requirements: a. The Contractor shall provide all telephone, fax, high-speed wireless

internet and radio communication services required for performance of his work and pay all costs associated with such services.

2. Compressed Air:a. The Contractor shall provide all air compressors, fuels, lubricants, hoses,

piping and other apparatus for supplying air required for prosecution of his work.

3. Construction Power:a. The Contractor shall provide all energy for construction electric power,

welding, energizing space heaters and temporary lighting.b. Temporary power facilities shall conform to applicable safety and code

requirements, shall be constructed to provide proper clearances and minimum interference with construction, and shall be acceptable to the Owner.

c. All temporary electrical installations must be scheduled by the Contractor and shall be submitted to the Owner in writing with drawings. Approval will only be given in writing.

d. All temporary wiring shall conform to the NESC and Article 305 – TEMPORARY WIRING of the National Electrical Code.

4. Water:a. The Contractor shall provide sanitary drinking water facilities for his

employees including coolers, ice, disposable cups and a trash barrel at each water cooler. Each dispenser shall be emptied, cleaned and refilled at the start of each day, and personnel shall be assigned to assure maintenance of the water supply.

5. Sanitary Facilities:a. The Contractor shall furnish and maintain sanitary facilities, including

chemical toilets, and garbage removal facilities, for the use of the Contractor’ personnel, and other authorized personnel.



6. Security:a. The Contractor shall be responsible for all security affecting the

execution of his own work including materials.

7. Fire Protectiona. The Contractor shall provide and maintain adequate fire protection

equipment in each area for which he is responsible, including each temporary office and storage area he uses. Fire protection equipment size and quantity shall satisfy all insurance requirements.

PART 3 – EXECUTION (NOT APPLICABLE)



SECTION 22080DUCT SYSTEM

PART 1 - GENERAL

1.01 SCOPE

A. This section covers furnishing and field installation of a 345-kV Concrete Encased Duct Bank System. Duct bank detail performance drawings are provided in the construction drawings.

B. The Contractor shall construct a complete duct bank system to include all conduits, including transitions between types of conduits, conduit spacers, tracer wires and warning tape, as shown on the drawings and/or as specified.

C. The Contractor must notify Owner and the Engineer thirty (30) days prior to duct proofing to allow for travel arrangements to be made to witness the proofing.

D. The conduit accessories shall be of the same type material as the conduit selected.

E. The Contractor shall install all conduit, fittings (i.e., couplings, adapters, end bells, etc.), and plastic cement.

F. All duct line installation work shall be subject to inspection and approval by Owner.

G. Prior to duct installation, the trench shall be subject to inspection and approval by Owner. Bottom of trench shall be firm and not muddy. If water is present in the bottom of the trench, the Contractor shall make every effort to remove the water. If the bottom of the trench is muddy, the Contractor shall place gravel as necessary to firm up the trench bottom.

H. Prior to thermal concrete installation, the duct bank shall be inspected and approved by Owner.

I. The Contractor is responsible for furnishing all necessary materials for furnishing the complete duct bank system. This shall include all hardware and miscellaneous materials as required.

J. Prior to installation, all materials provided by the Contractor shall be submitted to the Owner for acceptance.

PART 2 - PRODUCTS

2.01 PVC CONDUIT

A. Conduit to be installed in the trench shall be Schedule 40 electrical grade polyvinyl chloride (PVC). Conduit shall be manufactured in accordance with the latest revision of NEMA TC-2 and ANSI/UL651 specifications.

B. The PVC conduit shall be provided in 20 foot lengths with bell and spigot.



C. For PVC bell and spigot conduit, the spigot end shall be chamfered and the insertion ring marked by the manufacturer, prior to delivery to the job site.

2.02 INNER DUCTS

A. Three (3) one inch (1”) SIDR 9 TRUE ribbed wall HDPE Dura-Line™ inner ducts or Owner approved acceptable equal, to be installed by Contractor, within the 4” communication conduit. Inner duct shall be of a smooth outer wall construction with longitudinally-orientated ribbed inner walls to facilitate low friction cable pulling. 1. Each inner duct shall have a pulling tape installed per pulling plan.

2.03 CONDUIT STORAGE AND TRANSPORTATION

A. Cover conduit that is to be stored for more than two (2) weeks within 24-hours of receiving.

B. Provide support for the full length of the conduit when transporting or storing long lengths (20'). Do not permit unsupported overhang.

2.04 MULE TAPE

A. After completion of cleaning and testing of the duct line, the Contractor shall install in each duct run a mule tape pull line (AANCO Dandy Line TIFF 2,500 lbs.) or equivalent and plug both ends of each duct with plugs.

PART 3 - EXECUTION

3.01 DUCT BANK

A. The duct bank system is described as follows:

1. All concrete encased duct banks shall be per the detail drawings. Owner-approved conduit spacers will be placed at least every five (5) feet, or as required on tight radius bends. Spacers must be a minimum of 15 inches away from coupling and joints. Thermally tested concrete that have been previously approved by Owner shall be used.

2. All ducts, hangers system, and duct coverings shall be attached to various bridges per the detail drawings.

B. All power cable ducts shall be cleaned to the satisfaction of the Owner using tight fitting rag bundles, tested (mandrel), mule tape installed and plugged at conduit terminations.

C. Transmission duct bank concrete shall be periodically tested for thermal requirements at Contractor’s expense as specified in this specification.

D. At no time shall reinforcing steel be placed around a single phase of conduit.



E. Concrete for encased duct lines shall be cured for a minimum of 4 hours before backfilling can commence.

F. All ducts shall be mandreled in the presence of an Owner Authorized Representative or the Engineer. The Contractor shall notify Owner thirty (30) days prior to starting the work. Written documentation of the completion and acceptance of the testing shall be provided to the Owner within one (1) days after the completion of the testing.

3.02 CONDUIT INSTALLATION

A. A fine tooth wood saw may be used to cut the conduit. Make a square cut and remove all burrs. Inside edge must be beveled such that a ridge does not occur that could damage cable polyethylene jacket. All field cuts must be accomplished in the presence of an Owner representative and shall be chamfered to the satisfaction of the Inspector.

B. Wipe all foreign matter off the sockets of the fittings and the edges of the conduit with clean cloth.

C. Field bending shall not be permitted for bends less than a fifty (50) foot radius. All bends except the riser bends shall be greater than fifty (50) foot unless otherwise shown on the drawing or approved by the Engineer. All bends less than fifty (50) foot shall be factory bent.

D. Where directional changes are required, the conduit shall be bent in smooth, uniform bends and in method to not cause any kinks in the conduit. Bends shall be made to the minimum radius as required by the project drawings and shall not result in a reduced cross-sectional area. Prior to performing any bends in the field, the Contractor shall submit their bending procedure for review and acceptance by the Owner and Engineer.

E. Five degree (5o) couplings shall not be used at any time during the conduit installation.

F. Prior to connecting any factory bends or field bends to a conduit run, the conduit shall be mandreled to insure the bend is not kinked or the cross-sectional area has been reduced.

3.03 PVC CONDUIT SOLVENT-CEMENTED JOINTS

A. The PVC cement should be obtained from the conduit manufacturer. Thinners are not allowed.

B. Prior to joining the conduit, the joining ends shall be wiped clean of debris.

C. Apply a liberal and uniform coat of cement to the conduit for a length equal to the depth of the socket. Also, apply sufficient cement to wet the socket of the fitting. Avoid excess cement on the fitting, as it is wiped into the joint and tends to weaken the pipe. Do not use plastic bristle brushes.

D. Slip conduit into the socket of the fitting with a slight twist until it bottoms. Hold the joint for 15 seconds so the conduit does not push out of the fitting. Do not twist or drive the pipe after the insertion is complete. All conduit joined by cement shall have belled ends.



E. Cure the joined members for at least five (5) minutes before disturbing or applying stress to the joint. After this initial cure, care must be exercised in handling to prevent twisting or pulling the joint. In damp weather, increase this interval to allow for slower evaporation of the solvent. Where possible, assemble all conduit above ground and allow it to lay undisturbed while curing before lowering it into the ditch.

F. Wipe off the excess cement left on the outer shoulder of the fitting.

G. Another fitting or section of conduit may be added to the opposite end within two (2) minutes, if care is exercised in handling so that strain is not placed on the previous assembly.

H. Assemble above ground, any joint included in a section of conduit to be bent in the ditch, and allow it to lay undisturbed for at least two (2) hours before installation. In cases where a plastic connection is made with the union under stress due to misalignment or other factors, stake it out to relieve stress on the joint until the conduit is backfilled or encased.

I. To minimize accidental mechanical damage, do not expose conduit in an open trench longer than is absolutely necessary.

3.04 PLASTIC CONDUIT TEMPERATURE

A. Expose all plastic conduit and fittings to the same temperature conditions for a reasonable length of time before assembly.

B. Precautions – Due to expansion and contraction of the plastic conduit of 1-1/2 inches per 100 feet for every 20°F change in the temperature, allow extra conduit footage at each tie-in for contraction when the conduit temperature is higher than that of the earth; or extra room for expansion if the converse condition exists.

3.05 PLASTIC CONDUIT TERMINATION

A. End bells shall be used to terminate all conduits ending in an underground structure

B. The terminated ends of the conduit in an underground structure must be free of support for a distance of at least ten (10) feet from the structure. The conduit will be aligned and supported inside the structure with proper spacing.

C. The ends of the conduit shall be sealed with a plastic cap, plug, or approved substitute at the end of each day’s work, when work on duct installation has to be interrupted, or where ducts may be submerged in water.

3.06 INSPECTION

A. The completed duct lines shall be cleaned and field tested and pulling lines and plugs installed before final acceptance. The Contractor shall notify Owner a minimum of 30 days before starting this work. A representative of Owner and the Cable Contractor shall be present at all times until the cleaning, and testing are completed and pulling lines and plugs are installed to



his/her satisfaction. The Cable Contractor must provide written approval of acceptance of the duct bank system before Owner will provide final acceptance.

B. Contractors shall pull a wire brush and rag bundle through each conduit run to ensure duct is free of sand, dirt, and debris. This shall be performed to the satisfaction of Owner’s Inspector.

C. The wire brush for cleaning the duct shall be a standard duct wire brush, and the diameter shall be the same as the inside diameter of ducts to be cleaned.

D. The Contractor shall pass a bullet-shaped wooden or metallic test mandrel through the entire length of each duct run of the duct line to test for freedom of burrs and obstructions.

E. The test mandrel shall be approved by the Owner and made of hardwood or Owner-approved metal, 14 inches long with a diameter 1/2-inch less than the inside diameter of the duct or otherwise required by the cable manufacturer. At Owner’s discretion, Owner may provide the mandrel.

F. Scarring found on the mandrel deeper than 1/32 inch, other than that caused by normal abrasion between the duct line and bottom of the mandrel, shall be taken to indicate that burrs and/or obstructions are present in the duct run. Owner inspector shall determine when the mandrel shall be re-run. The Contractor shall remove such burrs and/or obstructions after which the test mandrel is passed through again. The process will be repeated until a satisfactory result is obtained.

G. After completion of cleaning and testing of the duct line, the Contractor shall install in each duct run a mule tape pull and plug both ends of each duct with hydrostatic plugs.



SECTION 22100CONCRETE

PART 1 – GENERAL

1.01 SCOPE

A. This section shall apply to thermal concrete for use in the duct bank. The furnishing, transporting and placing of the concrete; and curing and finishing the duct bank shall conform to the requirements specified herein.

B. Concrete for the duct bank must be thermally tested prior to placement. The test results must be verified and concrete mixture approved by the Owner. Each concrete truck shall provide a batch mixture ticket, upon request by the Owner, prior to concrete placement. If truck driver does not have batch mixture ticket, truck may be rejected.

1.02 REFERENCE STANDARDS

A. IEEE Std 442 IEEE Guide for Soil Thermal Resistivity Measurements

B. American Society for Testing and Materials (ASTM): ASTM C33 “Standard Specification for Concrete Aggregates”

1.03 QUALITY ASSURANCE

A. Qualification of Manufacturers:

1. Manufacturers of the products specified for work under this Section shall be in the business of manufacturing similar products and shall be able to provide a history of successful production of the specified products.

2. Inspection: Completed facilities shall be approved by the Owner before installation of cable and equipment. Corrective work shall be performed at no additional cost to the Owner.

PART 2 – PRODUCT

2.01 MATERIALS

A. Portland Cements: Cement for all classes of concrete shall conform to the requirements under ASTM C150 “Standard Specification for Portland Cement”.

B. Aggregates:

1. Aggregates shall conform to the specifications of ASTM C33 for use in concrete and ASTM C144 for use in masonry mortar.

2. The maximum aggregate size for use in thermal concrete shall be 3/8 inch.



3. Fine Aggregate. Fine aggregate shall be clean, hard, dense, free of foreign matter and shall consist of beach sand, manufactured fines, or a combination thereof.

4. Coarse Aggregate. Coarse aggregate shall consist of crushed stone or gravel manufactured from clean, hard, tough, dense, durable rock and free from adherent coatings.

C. Water: Water shall be clear and free from injurious amount of oil, acid, salt, alkali, organic matter, or other deleterious substances.

D. Admixture: Calcium may not be used. No admixture of any kind shall be used without the written consent of the Owner.

2.02 CONCRETE STRENGTH AND QUALITY

A. Unless specified otherwise on the plans, all thermal concrete shall meet the following requirements:

1. Strength: minimum compressive strength 3000 psi at 28 days2. Slump: 7" ± 1"3. Aggregate: maximum size 3/8” 4. Admixture: prior approval required5. No air entrainment allowed


3.01 MIXING AND PLACING

A. Ready-Mixed Concrete.

1. Ready-mixed concrete shall be used and the mixing, transporting, placing, and the quality shall meet the requirements as specified under ASTM C94.

B. Placing Concrete:

1. The Owner shall be notified twenty-four (24) hours before placing any concrete. Concrete shall be placed only in the presence of the Owner’s representative.

2. Concrete shall be batched only in such quantities as are require for immediate use and placement. Any concrete, as determined by the Owner, having initial set before placing and finishing shall be discarded and shall not be used for the work. No remixing with water or with other materials will be permitted once the initial set has taken place.

3. Concrete shall be placed as nearly as is possible in its final position so as to avoid segregation of the materials. The placement shall be completed within thirty-(30) minutes after water is first added to the mix. However, when the concrete is continually agitated, the time may be extended to one and one-half (1-½) hours. Retempering will not be permitted after the concrete has stiffened.



4. Concrete shall be placed on clean, damp surfaces, free from water, and in horizontal layers not exceeding eighteen (18) inches in thickness.

5. Concrete shall not be dropped a distance of more than five (5) feet unless approved in writing by the Owner.

6. Unless otherwise authorized, all concrete shall be compacted by use of hand spades. The spade shall be inserted into the fresh concrete to the level of the bottom of the excavation on both sides of each row of the trench and at intervals not greater than nine (9) inches along the trench. Concrete vibration shall only be done upon receipt of written approval by the Owner.

7. Concrete construction joints shall be made at the completion of each day’s pour. The joint shall be as close to 45 degrees as possible with the conduit extending a minimum of two feet from the end pour. An adjacent pour may be made at the discretion of the Contractor if previously approved by the owner.

C. Surface Finishes:

1. All concrete surfaces shall be wood float finished.

D. Curing:

1. Curing operations shall be started as soon as the concrete has attained initial set. The method and length of curing shall be approved by the Owner.

2. Concrete for duct bank shall be cured for seventy-two (72) hours before motor traffic is allowed to pass over it.

E. Cold Weather Concreting:

1. All concrete materials and all forms and ground, with which the concrete is to come in contact with, shall be free from frost.

2. When atmospheric temperature is below 40°F, the aggregates and/or water for the concrete shall be heated uniformly such that the temperature of the aggregates and water mixture at the time of introduction of the concrete and the temperature of the concrete at the time of placement shall be not less than 60°F or more than 95°F. The aggregates shall be free from ice, frost and frozen lumps when introduced into the mixture.

3. All concrete which has not attained an age of twenty-four (24) hours before the atmospheric temperature falls below 40°F, shall be covered with frame work with satisfactory covering material and then covered with at least six (6) inches of loose dirt or other insulating material that will maintain an air temperature surrounding the new concrete at a minimum of 50°F during the curing period. It shall be the Contractor’s responsibility to see that the concrete test cylinders receive the same protection as the concrete footings.

4. Concrete placement will not be allowed to continue when the atmospheric temperature is 38°F and falling. Concrete placement will not be allowed to begin until the atmospheric temperature is 34°F and rising. Cold weather concrete work can be approved, but Contractor must submit procedure and receive Owner approval prior to pour.



3.02 FORMS

A. The finished forms shall be true to the required dimensions and grades, with smooth surfaces, mortar tight joints, and of sufficient strength to resist springing out of shape during the placing of concrete. The inside surfaces shall be thoroughly coated with commercial quality form oil. Forms may be of wood, metal, or any other material and shall be free from defects. All exposed surfaces shall be formed with new plywood or with metal.

3.03 TESTING

A. The following field tests shall be made at the point of placement in the presence of the Owner. Equipment, supplies and qualified personnel for field-testing shall be supplied. Tests shall be performed by an Owner-approved independent testing lab retained and paid for by the Contractor.

1. Slump:a. A slump test shall be made each day or at the discretion of the Owner.

Slump shall be in accordance with ASTM C143.2. Air Content:

a. Air content shall be determined from each test cylinder taken, in accordance with ASTM C231. Air content does not need to be taken in the field but shall be reported on certified test reports on cylinders taken.

3. Compression Tests:a. Two compression test cylinders shall be made for 300 lineal feet of duct

bank. One (1) cylinder of each set shall be tested at seven (7) days with the other cylinder being tested at 28 days.

b. Test cylinders shall be marked or tagged with the date, temperature, time of day cylinders were taken, location taken, delivery truck or batch number and the slump.

4. Thermal Testsa. Two (2) test cylinders shall be made for every 300 lineal feet of duct

bank and labeled with the stationing at which the cylinder was made. This shall be sent to Geotherm, Inc., or Owner-approved equal, for testing. The Contractor shall be responsible for all costs associated with this testing.

5. Report:a. The Contractor shall furnish to the Owner certified reports of all tests.

3.04 SUBMITTALS

A. Concrete mix and specific quarry from which the testing was derived shall be submitted to the Owner based on testing done by an approved laboratory.

B. Thermal dry-out curves showing the thermal resistivity as a function of moisture shall be provided to the Owner.



C. The Contractor shall furnish to the Owner certified reports of all tests.

3.05 LABORATORY QUALIFICATIONS

A. Geotherm, Inc. shall provide thermal testing and concrete design or an Owner approved alternate testing laboratory.

B. An Owner approved independent testing laboratory shall be contracted with to provide the cylinder preparation, site testing and compression testing.



SECTION 22140EARTHWORK

PART 1 – GENERAL

1.01 SCOPE

A. This Section covers general earthwork and includes preparation of the construction areas; removal and disposal of debris; removal of vegetation from within the designated workspace areas that would otherwise impede construction activities; excavation and trenching; the handling, storage, transportation, and disposal of excavated material; sheeting, shoring, and protection work; preparation of subgrades; protection of adjacent construction; backfill; construction of fills and embankments; surfacing and grading; and other appurtenant work, all in accordance with applicable federal, state and local laws, ordinances, and codes.

B. Refer to Geotechnical Report for site conditions.

1.02 DEFINITIONS

A. Topsoil: Natural or cultivated surface-soil layer containing organic matter and sand, silt, and clay particles; friable, pervious, and black or a darker shade of brown, gray, or red than underlying subsoil; reasonably free of subsoil, clay lumps, gravel, and other objects more than 2 inches in diameter; and free of weeds, roots, and other deleterious materials.

1.03 MATERIALS OWNERSHIP

A. Except for materials indicated to be stockpiled, cleared materials shall become Contractor’s property and shall be removed from the site at the Contractor’s expense.

PART 2 – PRODUCTS

2.01 WARNING TAPE

A. Contractor shall furnish and install 6” wide red warning tape as shown on the drawings.


3.01 PREPARATION

A. Protect and maintain benchmarks and survey control points from disturbance during construction.

B. Provide erosion-control measures to prevent soil erosion and discharge of soil-bearing water runoff or airborne dust to adjacent properties and walkways.

C. Locate and clearly flag trees and vegetation to remain or to be relocated.



D. Protect existing site improvements to remain from damage during construction.

1. Restore damaged improvements to their original condition, as acceptable to Owner.

3.02 TREE PROTECTION

A. Erect and maintain a temporary fence around drip line of individual trees or around perimeter drip line of groups of trees to remain. Remove fence when construction is complete.

1. Do not store construction materials, debris, or excavated material within drip line of remaining trees.

2. Do not permit vehicles, equipment, or foot traffic within drip line of remaining trees.

B. Do not excavate within drip line of trees, unless otherwise indicated.

C. Where excavation for new construction is required within the drip line of trees, hand clear and excavate to minimize damage to root systems. Use narrow-tine spading forks, comb soil to exposed roots, and cleanly cut roots as close to excavation as possible.

1. Temporarily support and protect roots from damage until they are permanently relocated and covered with soil.

2. Coat cut faces of roots more than 1-1/2 inches in diameter with an emulsified asphalt or other approved coating formulated for use on damaged plant tissues.

3. Cover exposed roots with wet burlap and water regularly to prevent roots from drying out. Backfill with soils as soon as possible.

D. At Contractor’s expense, repair or replace trees and vegetation indicated to remain that are damaged by construction operations, in a manner approved by the Owner.

1. Contractor to employ a qualified arborist, licensed in jurisdiction where Project is located, to submit details of proposed repairs and to repair damage to trees and shrubs.

2. Replace trees that cannot be repaired and restored to full-growth status, as determined by the qualified arborist.

3.03 CLEARING AND GRUBBING

A. Remove obstructions, trees, shrubs, grass, and other vegetation to permit installation of new construction. Removal includes digging out stumps and obstructions and grubbing roots.

1. Do not remove trees, shrubs, and other vegetation designated to remain or to be relocated.



2. Cut minor roots and branches of trees designated to remain in a clean and careful manner where such roots and branches obstruct installation of new construction.

3. Completely remove stumps, roots, obstructions, and debris extending to a depth of 18 inches below exposed subgrade.

4. Use only hand methods for grubbing within drip line of remaining trees.

B. Fill depressions caused by clearing and grubbing operations with satisfactory soil material, unless further excavation or earthwork is indicated.

1. Place fill material in horizontal layers not exceeding 8-inch (200 mm) loose depth, and compact each layer to a density equal to adjacent original ground.

3.04 TOPSOIL STRIPPING

A. Remove sod and grass before stripping topsoil.

B. Strip topsoil to whatever depths are encountered in a manner to prevent intermingling with underlying subsoil or other waste materials.

1. Strip surface soil of unsuitable topsoil, including trash, debris, weeds, roots, and other waste materials.

C. Stockpile topsoil materials away from edge of excavations without intermixing with subsoil. Grade and shape stockpiles to drain surface water. Cover to prevent windblown dust.

1. Limit height of topsoil stockpiles to 72-inches.2. Do not stockpile topsoil within drip line of remaining trees.3. Dispose of excess topsoil as specified for waste material disposal.4. Stockpile surplus topsoil and allow for re-spreading deeper topsoil.

3.05 DISPOSAL

A. Remove surplus soil materials, unsuitable topsoil, obstructions, demolished materials, and waste materials, including trash and debris, and legally dispose of them.

3.06 SHEETING AND SHORING

A. The stability of previously constructed structures and facilities shall not be impaired or endangered by excavation work. Previously constructed structures and facilities include all transition and termination structures.

B. Adequate sheeting and shoring shall be provided to protect and maintain the stability of previously constructed structures and facilities and the sides of excavations and trenches until they are backfilled. Sheeting, bracing, and shoring shall be designed and built to withstand all loads that might be caused by earth movement or pressure and shall maintain



the shape of the excavation under all circumstances. Drawings of all shoring details (as required by OSHA regulations) shall be provided to the Owner prior to excavation.

3.07 OVER EXCAVATION

A. Material excavated beyond the limits of the trench details shall be backfilled using thermally approved backfill.

3.08 SITE PREPARATION

A. Subgrades for permanent construction, including subgrades for fills and embankments, shall be stripped of all surface materials to include all topsoil.

B. All combustible and hazards waste materials shall be removed from the construction areas. Open burning is not permitted.

3.09 FILLS AND EMBANKMENTS

A. If, after excavation of trenches or pits, additional fill material is necessary, it shall be of the same thermal backfill required previously. Surface subgrades shall be compacted and well bonded to the previous layers of fill. All material deposited in subgrades shall be earth only and shall be free from rocks or stones, debris, and other objectionable materials.

3.10 STRUCTURE AND TRENCH SUBGRADES

A. Subgrades for the bottom of trenches shall be firm, dense, free from mud, thoroughly compacted, and sufficiently stable to remain firm and intact. Compaction shall be to at least 95 percent of the maximum dry density at optimum moisture content as determined by ASTM D1557 or to meet local codes.

B. Subgrades that are otherwise solid, but become mucky on top due to construction operations, shall be stabilized by reinforcing them with one (1) or more layers of crushed rock or gravel.

C. The finished elevation of stabilized structure subgrades shall not be above the subgrade elevations indicated on the drawings.

3.11 STRUCTURE BACKFILL

A. Backfill around the outside of structures shall be deposited in layers not to exceed six (6) inches in uncompacted thickness. Backfill shall be mechanically compacted to at least 95 percent of the maximum dry density. The material shall be placed at optimum moisture content as determined by ASTM D1557. Compaction of structure backfill by rolling will be permitted provided the desired compaction is obtained and damage to the structure is



prevented. Compaction of structure backfill by inundation with water will not be permitted.

B. Backfill material shall be composed of thermally approved backfill only. Backfill and surface subgrades may be earthy fills not to exceed one (1) foot in thickness, and free from rock, stone, debris, and any other objectionable material, unless otherwise specified.

C. No tamped, rolled, or otherwise mechanically compacted backfill shall be deposited or compacted in water.

D. All subgrade backfill material shall consist of loose earth having a moisture content required to obtain the specified density of the compacted soil. Moisture content shall be distributed uniformly. Water added for correction of moisture content shall be distributed uniformly prior to compaction. Granular material shall be wet, not just damp, when compacted.

3.12 TRENCH EXCAVATION

A. Trench excavation shall be open cut from the subgrade surface.

B. All trenching shall comply with OSHA regulations 29 CFR 1926 dated July 1, 2007 or latest revision.

C. Trench excavated materials having an organic content shall be stockpiled along the trench separately from excavated materials authorized for use as subgrade backfill. This organic material shall be disposed of and not used as backfill.

D. All excavated material deemed unacceptable for use as fill material shall be hauled away to a Contractor specified disposal site.

3.13 TRENCH WIDTHS

A. Trenches shall be excavated to a minimum width that will provide adequate working space for safe and proper duct bank installation.

B. Where necessary and applicable to reduce earth load on trench banks to prevent sliding and caving, banks may be cut back on slopes that shall not extend lower than one (1) foot above the top of the duct bank.

3.14 MECHANICAL EXCAVATION

A. Mechanical equipment shall not be used in locations where its operation would cause damage to buildings or structures above or below ground. Hand excavating methods shall be used in these locations.



3.15 TRENCH DEPTH

A. Duct bank trenches shall be excavated to the depth shown on the drawings.

3.16 TRENCH BACKFILL

A. Trench backfill shall be compacted for the full depth of the trench above the duct bank.

B. Backfill material shall be either trench excavated material or material furnished by the Contractor from his own sources, and shall be acceptable to the Owner. Any backfill material other than trench excavated material shall have a thermal resistivity of 70° C·cm/W at 6% moisture content.

C. Backfill shall be placed in uniform layers not exceeding eight (8) inches in uncompacted thickness. Increased layer thickness may be permitted for noncohesive material, if the specified compacted density is obtained. The method of compaction and the equipment used shall be appropriate for the material being compacted and shall not transmit damaging shocks to the cable. Unless specifically stated otherwise, trench backfill shall be compacted to not less than 95 percent of the maximum dry density as determined by ASTM D1557.

3.17 FINAL GRADING

A. After all construction work has been completed, all ground surface areas disturbed by construction or construction plant and operations shall be graded. The grading shall be finished to the contours and elevations indicated on the drawings or, if not indicated, to the matching contours and elevations of the original, undisturbed ground surface. The final grading shall provide smooth uniform surfaces and effective drainage of the ground areas.

B. Fills, embankments, and backfills that settle or erode before final acceptance of the work, and structures, shall be repaired by the Contractor at the Contractor's expense. The settled or eroded areas shall be filled, compacted, and graded to conform to the elevation indicated on the drawings or to the elevation of the adjacent ground surface. Damaged facilities shall be repaired in a manner acceptable to the Owner.

3.18 DISPOSAL OF MATERIALS

A. Surplus earth and materials not suitable for the work shall be spoiled in a manner and location selected by the Contractor and acceptable to the Owner. Disposal shall be in accordance with all federal, state, and local requirements pertaining to construction landfills.



SECTION 22175DEWATERING

PART 1 – GENERAL

1.01 SCOPE

A. The Contractor shall be responsible for the removal of all water entering any excavation, whether from natural ground water conditions or from weather runoff in order to maintain trenches, shaft excavations, structural excavations and foundation beds in a stable condition.

B. Protecting work against surface runoff.

C. Disposing of removed water in accordance with all applicable local, state, and federal regulations.

D. The Contractor shall be responsible for designing, permitting and executing a dewatering system capable of controlling existing ground water conditions and any anticipated water from a weather event.

1.02 RELATED DOCUMENTS

A. Drawings and general provision of the Contract apply to this section.

B. Refer to Geotechnical Report for site conditions.

1.03 REFERENCES

A. ASTM D698 – Test Methods for Moisture-Density Relations of Soils and soil-Aggregate Mixtures, Using 5.5lb Rammer and 12-inch Drop.

B. Federal Regulations, 29 CFR Part 1926, Standards-Excavation, Occupational Safety and Health Administration (OSHA).

C. Federal Register 40 CFR Part 122, EPA Administered Permit Programs (NPDES), Storm Water Discharge.

1.04 DEFINITIONS

A. Ground water control includes both dewatering and depressurization of water-bearing soil layers.

1. Dewatering includes lowering the water table and intercepting seepage that would otherwise emerge from slopes or bottoms of excavations, or into tunnels and shafts, and disposing of removed water. The intent of dewatering is to increase stability of trench excavations and excavated slopes; prevent dislocation



of material from slopes or bottoms of excavations; reduce lateral loads on sheeting and bracing; improve excavating and hauling characteristics of excavated material; prevent failure of heaving of the bottom of excavations; and to provide suitable conditions for placement of backfill materials and construction of structures and other installations.

2. Depressurization includes reduction in piezometric pressure within strata not controlled by dewatering alone, as required to prevent failure of heaving of excavation bottom or instability of trench excavations.

B. Excavation drainage includes keeping excavation free of surface and seepage water.

C. Surface drainage includes use of temporary drainage ditches and dikes and installation of temporary culverts and sump pumps with discharge lines as required to protect the work from any source of surface water.

D. Equipment and instrumentation for monitoring and control of the ground water control system includes piezometers and monitoring wells, and devices, such as flow meters, for observing and recording flow rates.

PART 2 - PRODUCT

2.01 EQUIPMENT AND MATERIALS

A. Equipment and materials are at the option of the Contractor as necessary to achieve desired results for dewatering. Selected equipment and materials are subject to review of the Owner through submittals as indicated herein.

B. Sump pumps, well points, deep wells or sock drains, where used, must be furnished, installed and operated by an experienced contractor regularly engaged in ground water control system design, installation and operation.

C. All equipment must be in good repair and operating order.

D. Sufficient standby equipment and materials shall be kept available to ensure continuous operation, where required.

PART 3 - EXECUTION

3.01 PERFORMANCE REQUIREMENTS

A. Conduct subsurface investigations to identify ground water conditions and to provide parameters for design, installation and operation of ground water control systems.

B. Design a ground water control system where open excavations will be affected by ground water entry or where ground water may result to excavation instability. Design a ground



water control system, compatible with requirements of Federal Regulations 29 CRF Part 1926 to produce the following results:

1. Effectively reduce the hydrostatic pressure affecting open excavations.2. Develop a substantially dry and stable subgrade for subsequent construction

operations.3. Preclude damage to adjacent properties, buildings, structures, utilities installed

facilities and other work.4. Prevent the loss of fines, seepage, boils, quick condition, or softening of the

foundation strata.5. Maintain stability of sides and bottom of excavations.

C. Provided ground water control systems may include single-stage or multiple-stage well point systems, sump pumps, deep wells, sock drains or combinations of these equipment types.

D. Provide drainage of seepage water and surface water, as well as water from any other source entering the excavation. Excavation drainage may include placement of drainage materials, such as crushed stone and filter fabric, together with sump pumping.

E. Provide ditches, berms, pumps and other methods necessary to divert and drain surface water from excavation and other work areas.

F. Locate ground water control and drainage systems so as not to interfere with utilities, construction operations, adjacent properties, or adjacent water wells.

G. Assume sole responsibility for ground water control systems and for any loss of damage resulting from partial or complete failure of protective measures and any settlement or resultant damage caused by the ground water control operations. Modify ground water control systems or operations if they cause or threaten to cause damage to new construction, existing site improvements, adjacent property, or adjacent water wells, or affect potentially contaminated areas. Repair damage caused by ground water control systems or resulting from failure of the system to protect property as required.

3.02 SUBMITTALS

A. Submit a Ground Water and surface Water Control Plan for review by the Owner prior to start of any field work.

3.03 ENVIRONMENTAL REQUIREMENTS

A. Comply with requirements of agencies having jurisdiction.

