CONSOLIDATED EDISON CO. OF NEW YORK, INC. 4 IRVING PLACE NEW YORK, NY DISTRIBUTION ENGINEERING DEPARTMENT NON-NETWORK SYSTEMS SECTION

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1 CONSOLIDATED EDISON CO. OF NEW YORK, INC. 4 IRVING PLACE NEW YORK, NY DISTRIBUTION ENGINEERING DEPARTMENT NON-NETWORK SYSTEMS SECTION SPECIFICATION EO-6224 REVISION NO. 10 DECEMBER 2005 TRENCHING REQUIREMENTS FOR INSTALLING URD CABLES IN CONDUIT OR DIRECT BURIED AND JOINT TRENCHING FILE: CONSTRUCTION STANDARDS MANUAL NO. 3: SECTION 16 URD MANUAL NO. 22, SECTION 2: CABLES URD MANUAL NO. 24, SECTION 2: CABLES TARGET AUDIENCE URD CONSTRUCTION NESC 2002 REFERENCE SECTION NO. 35

2 CONSTRUCTION STANDARDS EO-6224 REVISION 10 TABLE OF CONTENTS SECTION DESCRIPTION 1.0 PURPOSE 2.0 APPLICATION 3.0 GENERAL REQUIREMENTS 4.0 LOCATION OF TRENCHES 5.0 TRENCH SIZES 6.0 REQUIREMENTS FOR CABLE PROTECTION 7.0 PRIMARY AND SECONDARY CABLES INSTALLATION 8.0 BACKFILL FOR TRENCHES 9.0 SUPPLY TO STREET LAMPPOSTS 10.0 LOCATION OF URD VAULTS AND SPLICE BOXES FOR SUBSURFACE TRANSFORMERS 11.0 LOCATION OF BOX PADS AND SPLICE BOXES FOR PAD MOUNTED TRANSFORMERS 12.0 EXCAVATION AND BACKFILL FOR URD VAULTS, SPLICE BOXES, AND TRANSFORMER FIBERGLASS BOX PADS 13.0 INSTRUCTIONS FOR DIGGING AFTER ELECTRIC CABLES ARE INSTALLED 14.0 IDENTIFICATION OF BURIED ELECTRIC CABLES OR CONDUITS 15.0 PRIVATE STREETS ON PRIVATE PROPERTY 16.0 SEPTIC TANK AREAS 17.0 REFERENCES

3 CONSTRUCTION STANDARDS EO-6224 REVISION 10 TRENCHING REQUIREMENTS FOR INSTALLING URD CABLES IN CONDUIT OR DIRECT BURIED AND JOINT TRENCHING 1.0 PURPOSE This standard gives the requirements for installing URD cables in conduit or direct buried in public and private streets and in joint trenches where the same trench shall be used to install electric, gas, water, sewer and communication lines. 2.0 APPLICATION This specification applies to all Regions, except Manhattan. 3.0 GENERAL REQUIREMENTS The provisions in the specification apply to both public and private streets, unless stated otherwise. Private street, in this specification, refers to roadways in developments where the land surrounding each house is all corporationowned. For further discussion on private streets refer to paragraph For trench layout and/or excavation operation around trees, when practical, follow recommendations of the National Arbor Day Foundation (Field Pocket Guide for Qualified Utility Workers) to prevent or minimize damage to tree roots, bark or branches. For general use requirements of conduit system in URD developments, see EO Follow EO-3036 for installation of HDPE (High Density Polyethylene) conduits. 4.0 LOCATION OF TRENCHES 4.1 Trenches and/or excavation for equipment shall be laid out and dug in a manner so as to prevent or minimize damage to nearby/adjacent trees. Recommendations on minimum distance from trees, alternative conduit installation (e.g., tunneling or other approved no-dig techniques), possible spot tree trimming for construction equipment access, etc., are detailed on The National Arbor Day Foundation Guide. 4.2 The main trench for conduit or direct buried primary or secondary cables shall be located between the curb and the property line, where possible, depending upon sidewalk s dimensions and local municipality codes or recommendations of the National Arbor Day Foundation Guide. The trench shall be parallel to the roadway. Roadway crossing trenches

4 CONSTRUCTION STANDARDS EO-6224 REVISION 10 shall be perpendicular to the roadway and aligned to disturb the least amount of pavement. 4.3 Where a sidewalk is planned, the trench should preferably be located under the sidewalk in New York City as shown on Figure 1A and between the sidewalk and property line in Westchester as shown on Figure 1B. 4.4 Where no sidewalk is planned, the edge of the cable trench should be located minimum 4 feet from either the property line or curb (preferably from the property line if it can be identified to avoid accidental digging) as shown on Figure 1C. 4.5 Paragraphs 4.2, 4.3 and 4.4 give the preferred trench locations. However, it may not be practical to locate the main trench as shown on Figures 1A, 1B and 1C. Some reasons are: Sidewalk locations cannot be obtained from New York City, or the local municipality or the developer; Sidewalks already exist before the construction begins; Interference with or inadequate separation from installed gas pipes; Interference with or inadequate separation from proposed or installed water pipes, sewer pipes or drainage system; High rock concentration; and Route adjustment is needed to prevent or minimize damage to existing trees during trenching operations. 4.6 If the main trench cannot be located as indicated in paragraphs 4.2, 4.3 and 4.4, the alternate locations are as follows, listed in order of preference, depending on the municipality Alternate locations when sidewalks are planned: a. Under sidewalk on side closest to the street (see Figure 1D); b. Between sidewalk and the property line (see Figure 1B), (preferred in Westchester);

5 CONSTRUCTION STANDARDS EO-6224 REVISION 10 c. Between sidewalk and the curb without interfering with sewers, catch basins or other public utilities; d. Under the street, one foot from the curb (see Figure 1E) without interfering with sewers, catch basins or other public utilities. In New York City the cable must be installed in Company approved conduits. This is the least preferred location Alternate locations when no sidewalks are planned: a. Between property line and the curb, minimum four feet from either the property line or the curb (preferably from the property line if it can be identified to avoid accidental digging and to leave space for trees planting along the curb). b. Under the street, one foot from the curb (see Figure 1E) without interfering with sewers, catch basins or other utilities. This is the least preferred location. 4.7 In New York City, prior to construction, the Company shall obtain sidewalk locations from the City s Department of Transportation (Bureau of Highways) and in Westchester from the local municipality. 4.8 All other alternate locations for the main trench require the approval of the region s Electric Operations Manager of Distribution Engineering. 5.0 TRENCH SIZES 5.1 The maximum depth and width of trench for secondary (including street light) and communication cables shall be as shown on Figure 2A-1 for direct buried or Figure 2A-2 for conduit installation. 5.2 The maximum depth and width of trench of primary, secondary, (including street light) and communication (telephone or CATV, etc.), shall be as shown on Figure 2B-1 for DBC or Figure 2B-2 for conduit installation. 5.3 The maximum depth and width of trench of primary, secondary (including street light) communication, gas or water shall be as per Figure 2C-1 for DBC and 2C-2 for conduit installation. 5.4 The maximum depth and width of trench for electric cables and/or secondary, street lighting and/or communication cables and gas pipes

6 CONSTRUCTION STANDARDS EO-6224 REVISION 10 shall be in accordance with Figure 2C-1 and 2E-1. Follow 2C-2 and 2E-2 for cables in conduit. Electric facilities shall be installed first at the bottom of the trench, along with gas lines, followed by communications and other lines. 5.5 In rock areas where bottoms of the cable trenches cannot be kept smooth, all trenches for direct buried cables and gas pipes shall be 4 inches deeper than shown on Figure 2A-1 through 3B-1 and backfilled according to paragraphs 8.1 and 8.2. For installation of conduit in rocky areas, follow EO Maximum depth and width of trench and minimum cover dimensions shall be maintained at all times regardless of whether the trench is jointly occupied, or whether the trench is dug to repair facilities. 5.7 Refer to EO-5571-B for typical installation of electric conduits and gas mains in common trench, and Dwg. # for trench excavation for direct buried HDPE conduits alone in a trench. 5.8 The trench depths specified in paragraphs 5.2 through 5.4 shall not exceed 48 inches for cable installation, unless it is necessary to avoid interference with other facilities, or in order to maintain minimum clearances between facilities. All depths shall be referenced to final grade over the trench. 6.0 REQUIREMENTS FOR CABLE PROTECTION 6.1 For cases, where the cable is installed direct buried between the curb and the property line, the installation can be done at there areas: Main trench; From main trench to curb in road crossings; From main trench to property line in service trenches. 6.2 The cables must be installed in conduit under the following conditions: Where cables cross under a roadway, sidewalk, driveway or parking lot. A nominal cover of 24 inches below grade shall be maintained. If due to subsurface conditions the cover is less than 24 (but never less than 18 ), protect the conduit and the cable with a 3/8 steel plate of same width as the trench.

7 CONSTRUCTION STANDARDS EO-6224 REVISION Where proper clearances between electric cables and other utilities cannot be obtained For road crossings where the roads are being paved before cable installation, or where conduit installation eliminates the need for stand-by crews by providing a more flexible work schedule For other field conditions as outlined on EO In New York City, service cable on customer s property shall be installed in a steel pipe or other approved conduit in accordance with the New York City Electrical Code (NYC Electrical code was merged with the National Electrical Code (NEC) in July 2003). The customer shall be required to extend the customer s conduit to the property line and connect to the company s approved conduit, and to seal the end with duct seal as specified on EO A coupling of adequate strength and proper size shall be used to firmly join the customer s or Company s conduits. In Westchester, service cable shall also be installed in Company approved conduit unless local municipal codes specify otherwise. 6.4 Duct locations shall be recorded on Company layouts. 6.5 A warning tape (c/s # ) shall be laid continuously in the trench at the bottom of the last 12 layer of backfill covering the cables in conduit or direct buried cables. 7.0 INSTALLATION OF PRIMARY AND SECONDARY CABLES 7.1 In most cases, the primary supply from each feeder consists of three cables, one for each phase. In this specification, each set of three primary cables is called a primary feed. 7.2 In a common trench two primary feeders can be installed with a minimum of 6 inches clearance from each other as shown in Figure 3A. When gas mains are also installed in the same common trench, the clearances shall be as shown in Figure 3B. Notes: 1. In the remaining paragraphs of this specification, street lighting cables are to be considered as secondary cables. Whatever applies to secondary cables shall be applicable to street lighting cables also.

8 CONSTRUCTION STANDARDS EO-6224 REVISION Install minimum #2 bare copper wire along 1/0 aluminum primary cable and minimum 2/0 bare copper wire for 4/0 aluminum primary cable. It shall be buried in close proximity of the jacketed cable and in continuous contact with earth. Install only one copper wire whether the primary is one phase or three phases. 7.3 Separation Between Electric, Communication and Gas Line and Other Facilities Minimum separations in inches between cables/conduits/pipes containing electric and communication cables, gas lines and other facilities shall be maintained as shown on Figures 2B, 2C, 2D, 2E and 3B for direct buried cable or cable-in-conduit. For proper protection of gas mains and services, refer to general specifications G-8100 & G At buried facility crossings, a minimum vertical separation of 12 inches shall be maintained between Company electric (direct buried or in-conduit) and/or gas lines and sewer and/or water pipes and/or any other underground facilities owned/installed by others. Direct buried cables are installed side by side. No separation is required between them except for two different primary feeders installed in the same trench (see Figure 3A). 8.0 BACKFILL FOR TRENCHES 8.1 All backfill material for trenches shall be clean, free of stones greater than 2 inches in diameter, cinders and ashes. A minimum 4 inches cushion of sand type 3/8 inch shall be placed beneath the cables where there is no gas pipe installed. Where there is gas pipe installed in the same trench a sand cushion of 4 inches shall be provided for both including rock areas. Backfill on top of cables up to 6 inches shall be sand type 3/8 inch in accordance with Purchase and Test Specification EO The trench shall be backfilled with sand type 3/8 inch to a height of 12 inches above the cables. It shall be compacted by hand tamping in no more than 12 inches wetted lifts. The remaining trench shall be backfilled with suitable backfill material type II and shall be machine tamped. 8.3 For cables installed in street trenches only refer to Construction Standards EO-1181 for backfilling requirements. For backfilling of trenches other than street, follow paragraphs 8.1 and 8.2.

9 CONSTRUCTION STANDARDS EO-6224 REVISION Place sand bags 6 x 6 x 12 between electric and gas to maintain required clearances. The sand bags shall be placed approximately fifteen feet apart. 9.0 SUPPLY TO STREET LAMPPOSTS 9.1 The street lighting cables are installed in the URD main trench (see Figures 1A to 1E) to a point within 2 feet from the proposed lamppost foundation. Where the cables leave the main trench to cross the street they are installed in an approved conduit in a road-crossing trench, to the lamppost foundation. The protection of these cables is in accordance with paragraph 6.0 (See Figures 1A to 1E). Each lamppost foundation furnished by the builder/customer shall have an approved driven ground rod. The grounded neutral of supply cables shall be connected to the lamppost base, and bonded to the lamppost conduit, if metallic, then all grounds shall be connected to the driven ground rod as per EO-5830-C, and in accordance with the New York City Electrical Code, or, in Westchester, according to local municipal codes. Company crews should not make final connections to the street lights unless the customer/builder submits written evidence to the Company that an approved driven ground rod has been installed and connected to the system ground at the base of the street lamppost as required. 9.2 A street lighting overlay approved by the municipality will be furnished by the builder indicating the location of the proposed street lights on private property and on which the City will indicate the location of the proposed street lights. In Staten Island, the Street Light Agreement between Consolidated Edison and the City of New York dated June 6, 1980 (or applicable latest date) shall be followed. 9.3 Supply for lampposts on private property shall be extended by the property owner from the easement line (see paragraph 15.5) to the lamppost(s), in accordance with the New York City Code or in Westchester, in accordance with local municipal codes LOCATION OF URD VAULTS AND SPLICE BOXES FOR SUBSURFACE TRANSFORMERS 10.1 A URD system with subsurface transformer uses direct buried or inconduit primary and secondary cables, and URD type transformer vaults and splice boxes. Refer to EO-2083 for more details on URD system The URD type transformer vaults and splice boxes shall be located between the property line and the curb, at least 6 inches from the property line and never in front of a driveway. This is shown on Figure

10 CONSTRUCTION STANDARDS EO-6224 REVISION 10 4A. If water or sewer pipes are obstructing the installation, the vault and splice box shall be installed in a non-obstructed area between the property line and the curb The transformer vaults and splice boxes shall be located on the side lot line between homes, whenever possible, and shall be aligned with lot line rather than directly in front of one customer s home Where sidewalks are present, the vault and splice box shall be installed as shown on figure 4B or 4C, depending on the dimensions of the sidewalk indicated. If there is not enough room to fit the vault and splice box in this area, some portion of the vault or box shall be in the sidewalk area, as shown on Figure 4B. Where necessary the splice box (with cover at grade level) may be located entirely within the sidewalk area, If water or sewer pipes are obstructing the installation, the vault and splice box shall be located between the sidewalk and curb. Vaults and boxes shall clear driveway areas. Wherever possible, a 5 ft. easement should be obtained from the builder to permit the splice box to be located out of the sidewalk area When paving around the vault or splice box, the following conditions shall be met: The final paving of the sidewalk shall not be more than 1/8 inch above or below the top of the vault grate or splice box cover The final paving of the sidewalk shall have a separation from the vault grate by at least 1/8 inch but no more than 1/4 inch, as shown on Figure 4B The transformer and splice box vault shall always be installed a minimum of: inches from the nearest gas pipe inches from the nearest liquid petroleum lines. Note: In Westchester, the minimum clearances shall be in accordance with municipal requirements The cables between the transformer enclosure and the main run shall be, in general, perpendicular from the main run.

11 CONSTRUCTION STANDARDS EO-6224 REVISION When field conditions or development layout preclude the installation of fiberglass transformer vaults between the curb and the customers property line, a precast concrete vault (Dwg. #305154) shall be placed in the street at about 12 away from the curb. The concrete vault shall be installed a minimum of four feet away from driveways LOCATION OF BOX PADS AND SPLICE BOXES FOR PAD MOUNTED TRANSFORMERS 11.1 The URD system utilizes mini-padmounted transformers (preferred method) as per EO-2083; uses direct buried primary and secondary cables or cables-in-conduits (as required); fiberglass transformer box pads and splice boxes (where required by the number of homes to be supplied) The box pads and splice boxes shall be located between the property line and the curb, minimum 3 inches from the property line, and minimum four feet from a driveway or curb (see Figure 6A). If water or sewer pipes obstruct this installation, the box pad and splice box shall be installed on customer s property, between a 5 feet easement line and the property line (see Figures 6B and 6C) The transformer fiberglass box pads shall be located on the side lot line between homes, whenever possible, and shall align with the lot line rather than directly in front of customer s home. The installation of the transformer box pad shall be in such a way that the front of the transformer will face the street Where sidewalks are present and sufficient space exists, the preferred location of the box pad and splice box shall be at least four feet from the sidewalk, whenever possible towards the property line in accordance with drawing EO A. A 5 feet easement shall be obtained on customer s property, where needed (see Figure 6B). Where necessary, the splice box (with cover at grade level) may be located entirely within the sidewalk area The box pad and splice box installation shall conform to the requirements outlined in paragraphs 10.1 through 11.4 and in accordance with drawings EO A and EO A.

12 CONSTRUCTION STANDARDS EO-6224 REVISION EXCAVATION AND BACKFILL FOR URD VAULTS, SPLICE BOXES, AND TRANSFORMER FIBERGLASS BOX PADS 12.1 The required excavation for installing submersible URD vaults and splice boxes shall be in accordance with Figure 6 and drawing EO A The required excavation for installing the transformer box pads shall be in accordance with Figure 7 and in accordance with installation drawing EO A All backfill material for U.R.D. vaults, splice boxes and box pads shall be free of stones greater than two inches in diameter and tamped by hand. Voids around/below the boxes/pads shall be eliminated INSTRUCTIONS FOR DIGGING AFTER ELECTRIC CABLES ARE INSTALLED 13.1 To prevent accidental dig-ups of buried or in-conduit electric cables during operations by non-company personnel (water, sewer, gas, communication cables or others), the Company shall be notified by the proper authorities before digging in accordance with New York State Industrial Code 753. Upon this notification, the Company shall provide assistance in locating the installed electric cables A permanent tag shall be affixed in accordance with EO D to transformer gratings of subsurface transformer and to the outer cover of the mini-padmounted transformers in accordance with EO The tag shall include a general warning that electric cables are in the area and that the one-call center of NYC or Westchester shall be contacted prior to digging in the area IDENTIFICATION OF BURIED ELECTRIC CABLES OR CONDUITS 14.1 Primary Cables The Company s primary cables shall consist of one, two or three cables (depending upon number of phases required) positioned close to each other and will have Property of Consolidated Edison stenciled on them Secondary Cables The Company s secondary cables shall be singlephase 3 wires or three phases 4 wire depending upon the required load. Single phase shall consist of three single leg cables (two plain black and the third wire is black with green or yellow stripes) wrapped around each other and three phase shall consist of four single leg cables (red, green, yellow and black) laid close to each other. All these cables shall have Property of Consolidated Edison stenciled on them.

13 CONSTRUCTION STANDARDS EO-6224 REVISION Street Lighting Cables The Company s street lighting cables shall consist of two single legs wrapped around each other and will have Property of Consolidated Edison stenciled on them Cables-in-conduit For cables-in-conduit cases, the conduits shall be prominently and permanently marked with the Electric Conduit logo and other related information as per EO PRIVATE STREETS ON PRIVATE PROPERTY 15.1 Private property in this specification means developments with private streets where the residences are individually owned, such as: Subdivisions with individual residences located on separate lots fronting on mapped roads, Condominiums with individual residential units surrounded by common areas with private access roads, Town Houses with front and rear yards (plus side yards for end units fronting on private roads, Cluster zoning with private roads and large open spaces held by homeowner s association For the above reasons, in privately owned developments of this type where the Company has elected to install its facilities, the following shall be established: In New York city a line, 10 feet to 15 feet from the curb line on each side of the roadway, and parallel to the roadway, driveways and parking areas shall be called the Property Line. The dimensions of 10 feet to 15 feet depend upon width of the roadway. All Company facilities shall be installed between the curb and the property line. In Westchester County property line can be farther from the curb depending upon municipality All requirements in this specification, as they apply to public streets, shall also apply to private streets Extensions All extensions into such development, that are not along roadways, shall be picked up and extended by the property owner from the easement line into the development for distribution. However, this policy shall not contradict any PSC rules for services and extensions for the new residential customers The Company shall supply secondary cables, for residential customers in accordance with EO Easements The Company shall obtain a non-exclusive easement from the builder or corporation or any other owner of the property in the development along whose private roads the Company elects to install its

14 CONSTRUCTION STANDARDS EO-6224 REVISION 10 facilities. This easement is recorded in county clerk s office. The builder or corporation or any other owner of the development must provide all line and grade stakes. The Company employees shall have access to such easement for the purpose of work related Jobs. This easement shall run with the land SEPTIC TANK AREAS Septic tank areas as referred to in this specification, are defined as areas where the chemical action resulting from septic seepage affects the Company cables REFERENCES 17.1 New York State Industrial Code Rule The following specification are listed for reference purposes: Spec No. Title Filed In EO-1100 EO-1181 EO-1136 Sealing of Service Ducts, Entrance and Bus Openings in Electrical Distribution Structures General Specification for Backfilling of Trench and Small Openings General Requirements for use of conduit system in URD Developments Manual No. 3 Manual No. 3 Manual No. 4 EO-2055 A.C. Services Manual No. 4 EO-4041 Operation of System Using URD T- Taps, Disconnects and In-line Jumper Modules EO-6228 EO-8085 Tagging and Identification of URD and Mini-pad Transformer Installations General Backfill and Bedding Material for Excavations G-8100 General Specification of Installation of Gas Services G-8005 General Specification for the Installation of Gas Distribution Mains Manual No. 3 Manual No. 3 Manual No. 6 Construction Stds. (Gas) Construction Stds. (Gas)

15 CONSTRUCTION STANDARDS EO-6224 REVISION The following drawings are listed for reference purposes: Spec No. Title Filed In Rectangular Splice Box for URD System Manual No Trench excavations for steel gas mains up to 350 P.S.I.G. Construction Stds. (Gas) EO A Installation of Enclosures and Cables for Residential Subsurface Transformer Manual No. 3 EO D URD Warning Tag Manual No. 3 EO A Installation of Box Pad, Splice Box and Cables for Mini-Padmounted Transformer (URD) Manual No. 3 EO B Adjustable Splice Box for URD System Manual No. 3 EO A Typical Installation for Mini-Padmounted Transformer Manual No. 3 S. Parasher/Luis Ortega Attachments: Figures 1 though 8 Signature on File Leeman Hong Acting Section Manager, Non-Network Systems Section Distribution Engineering Department REVISION 10 This specification supersedes EO This specification has been revised to comply with NESC 2002 and to include reference to National Arbor Day Foundation. Changed depths & width of trench from minimum to maximum values. Changed paragraphs 5.1, 5.2 and 5.3. Added note following paragraph 4.0. Added paragraphs 10.8 and Added Manual No. 24. Made other changes as marked by gray bar. Scheduled spec. review by FILE Construction Standards Manual No. 3, Section 16: URD Field Manual No. 22, URD, Section 2: Cables Field Manual No. 24, URD, Section 2: Cables

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