November 21, 1997

Contract \# **TW-0928**

SPECIAL SPECIFICATION

SECTION 16115-S

[EXTERIOR RACEWAYS, DIRECT BURY CABLES, MANHOLES]{.underline}

Page

[PART 1 - GENERAL]{.underline}

1.01 Scope 2

1.02 Related Sections 2

1.03 References 2

1.04 Submittals and Substitutions 3

[PART 2 - PRODUCTS]{.underline}

2.01 General 3

2.02 Conduit And Duct Systems - General 3

2.03 Metallic Conduit - General 4

2.04 Rigid Metal Conduit And Fittings 4

2.05 Intermediate Metal Conduit (Imc) And Fittings 4

2.06 Non-Metallic Conduit - Concrete Encased 4

2.07 Corrosion Protection 5

2.08 Direct Buried Cable - General 5

2.09 Manholes - General 5

2.10 Manholes - Precast Concrete 5

2.11 Manholes - Concrete Cast-In-Place 6

2.12 Manhole Accessories 6

[PART 3 - EXECUTION]{.underline}

3.01 Conduits - General 7

3.02 Concrete Encased Conduits 9

3.03 Direct Buried Cable - General 9

3.04 Manholes - Precast Concrete 9

3.05 Manholes - Cast-In-Place Concrete 9

3.06 Manhole Accessories 10

SPECIAL SPECIFICATION

SECTION 16115-S

[EXTERIOR RACEWAYS, DIRECT BURY CABLES, MANHOLES]{.underline}

# PART 1 - GENERAL

## 1.01 [SCOPE]{.underline}

> This specification covers the following items and accessory materials
> associated with these items: conduits, multiple conduits or duct
> banks, manholes, and risers. Construction practices during
> installation of these items are also covered to provide a reliable
> underground system.

## 1.02 [RELATED SECTIONS]{.underline}

A. Section 01300-S - Submittals

B. Section 02200-S - Earthwork.

C. Section 02510 - Asphalt Concrete Pavement

D. Section 03300-S - Cast-In-Place Concrete

E. Section 16120-S - Medium Voltage Cable

F. Section 16461-S - Pad Mounted Transformers

G. Section 16475-S - Primary System Safety Requirements

## 1.03 [REFERENCES]{.underline}

> The current editions of the referenced standards are a part of this
> specification.

A. [General]{.underline}

1\. ANSI/NFPA 70 - National Electrical Code.

2\. ANSI/IEEE C2 - National Electrical Safety Code.

3\. ASTM C-33 - Standard Specification for Concrete Aggregates.

B. [Conduit]{.underline}

1\. ANSI C80.1 Rigid Steel Conduit, Zinc Coated.

2\. UL 1242 and ANSI C80.6 - Intermediate Metal Conduit.

3\. NEMA RN1 - Polyvinyl Chloride (PVC) Externally Coated Galvanized
Rigid Steel Conduit and Intermediate Metal Conduit.

4\. NEMA TC2 - Electrical Plastic Tubing (EPT) and Conduit (EPC-40 and
EPC-80).

5\. ANSI/NEMA FB1 - Fittings, Cast Metal Boxes, and Conduit Bodies for
Cable Assemblies.

6\. NEMA TC3 - PVC Fittings for Use With Rigid PVC Conduit and Tubing.

C. [Manholes]{.underline}

1\. AASHTO Standard Specification for Highway Bridges.

2\. ANSI/ASTM A153 - Zinc Coating (Hot-Dip) on Iron and Steel Hardware.

3\. ANSI/ASTM A569 - Steel, Sheet and Strip, Carbon (0.15 maximum
percent), Hot-Rolled, Commercial Quality.

4\. ASTM A48 - Gray Iron Castings.

5\. STM A123 - Zinc (Hot-Galvanized) Coatings on Products Fabricated
from Rolled, Pressed, and Forged Steel Shapes, Plates, Bars, and Strips.

## 1.04 [SUBMITTALS and SUBSTITUTIONS:]{.underline}

> The Contractor shall submit catalog data as required per Sandia\'s
> Standard Specification, Section 01300-S. Substitutions of listed
> manufacturers shall be performed under the provisions of section
> 1600-S.

# PART 2 - PRODUCTS

## 2.01 [GENERAL]{.underline}

> All materials shall be new and applicable as listed, labeled, or
> approved by the Underwriters\' Laboratories, Inc. Defective equipment
> or equipment damaged in the course of installation or test shall be
> replaced or repaired in an approved manner.

## 2.02 [CONDUIT AND DUCT SYSTEMS - GENERAL]{.underline}

> Conduit and duct systems shall be of the type specified in the
> drawings and shall meet the requirements herein.

A. Conduits shall be joined in such a way as to prevent solid matter
from entering the joints. Joints shall form a continuous smooth interior
surface between joining conduit sections so that cable will not be
damaged when pulled past the joint.

B. Conduit installed on bridges, building roofs, or high temperature
areas shall incorporate expansion joints. Metallic conduit on a bridge
shall be grounded.

C. Pull boxes shall be 24\"W x 36\"L x 24\"D, unless otherwise specified
on drawings. \"PG\" style box assemblies of composolite as manufactured
by Quazite Corporation or approved equal. Material compressive strength
shall not be less than 11,000 PSI. Covers shall be heavy duty steel with
lock and logo as indicated. Boxes shall be stackable for extra depth.

D. Communication conduit for fiber optic cable shall have high capacity
flexible multiple channel innerduct manufactured by FO-DUCT or as
specified on contract drawings. The number of channels shall be
specified on the contract drawings.

## 2.03 [METALLIC CONDUIT - GENERAL]{.underline}

A. All steel conduits , RGS or IMC, in direct contact with the earth
shall receive a protective covering which shall be mechanically applied
in a factory or field plant especially equipped for this purpose. (Ref.
Section 2.07)

B. No conduit shall be covered with backfill until after the approval of
the Sandia Delegated Representative is obtained.

## 2.04 [RIGID METAL CONDUIT AND FITTINGS]{.underline}

A. Rigid steel conduit: ANSI C80.1.

B. PVC externally coated conduit: NEMA.RN 1; rigid steel conduit with
external 20 mil PVC coating and internal galvanized surface.

C. Fittings and conduit bodies: ANSI/NEMA FB 1; threaded type, material
to match conduit.

## 2.05 [INTERMEDIATE METAL CONDUIT (IMC) AND FITTINGS]{.underline}

A. Galvanized steel conduit: UL 1242 and ANSI C80.6.

B. Fittings and conduit bodies: ANSI/NEMA FB 1; use fittings and conduit
bodies specified above for rigid steel conduit.

## 2.06 [NON-METALLIC CONDUIT - CONCRETE ENCASED]{.underline}

A. Conduit: NEMA TC 2; schedule 40 PVC or schedule 80 PVC as indicated
on the drawings.

B. Fittings and conduit bodies: NEMA TC 3.

C. The concrete for the duct envelope shall conform in quality to all
requirements for placing and curing as described in the concrete
specifications. No concrete shall be poured until inspection is
obtained. Backfilling shall not be started until the concrete has set
for 5 hours. No duct shall be covered with backfill until after approval
is obtained.

D. For vertical stub-ups, horizontal bends, and any off-sets greater
than 22° in primary electrical and communication underground conduit
runs, use PVC-coated rigid steel or IMC factory bends. The minimum
radius shall be 24 inches for 3 inches and smaller conduit and 36 inches
radius for conduit larger than 3 inches. Half-lapped application of
corrosion protection tape is an acceptable alternate to PVC coating.
Standard radius conduit can be used for secondary electrical conduit as
specified on drawings.

## 2.07 [CORROSION PROTECTION]{.underline}

A. One of the following methods shall be used for metal conduit below
grade:

1\. 3M Scotchwrap 51, 20 mils thick used in conjunction with 3M
Scotchwrap Pipe Primer applied as recommended by manufacturer.

2\. Factory coated PVC on rigid conduit.

## 2.08 [DIRECT BURIED CABLE - GENERAL]{.underline}

A. Trench shall be opened to specified depth complete length of cable
run. Bottom of trench shall be leveled and tamped. Remove obstructions,
large rocks, and debris.

B. Bedding material for cable shall conform to the requirements of ASTM
C33 Fine Aggregate and shall be installed to a level uniform depth of
4\" in the trench prior to cable installation.

## 2.09 [MANHOLES - GENERAL]{.underline}

A. Manholes can be either precast concrete or cast-in-place as
designated on the drawings.

B. Drainage shall be provided to keep the manholes free of water during
construction.

## 2.10 [MANHOLES - PRECAST CONCRETE]{.underline}

A. Manufacturer shall have documented experience in the manufacture of
manholes for a minimum of three years.

B. Base course material shall be sand, 3 inches minimum compacted 95%.

C. Precast concrete: Air-entrained, 4000 psi minimum compressive
strength at 28 days.

D. Reinforcing: AASHTO HS-20; bridge loading.

E. Manhole Shape: As indicated on drawings.

F. Inside Dimensions: As indicated on drawings.

G. Wall Thickness: AASHTO HS-20; bridge loading.

H. Include 40-inch diameter grooved opening in top section for frame and
cover for power manholes and 36-inch diameter grooved opening for
communication manholes.

I. Frame and Cover Sections: 36-inch diameter clear opening for power
manholes and 30-inch diameter for communication manholes.

J. Include one 12-inch drain opening and two 1-inch ground rod openings
in base, one each diagonally opposite corners, not less than 6 inches or
greater than 12 inches from the wall.

K. Window for Duct Entry: Unless otherwise specified on drawings, 9-6
inch knockouts 3 rows of three on 8.56 inch centers shall be provided on
each wall with top row of knockouts not less than two feet below top of
manhole. Reference contract drawings for specific construction details.

L. Include cable pulling irons opposite each duct entry.

M. Include inserts for cable racks on three foot centers.

N. Include metal ladder in manhole, steps at 16 inches on center, ladder
bolted to manhole neck.

O. Ram-Nek, Kent Seal or approved equal sealants shall be used to seal
the joints in this manhole.

## 2.11 [MANHOLES - CONCRETE CAST-IN-PLACE]{.underline}

A. All provisions of Sections 2.10 and 2.12 unless specified in this
section.

B. Concrete: 3000 psi minimum compressive strength at 28 days in
conformance with requirements of Section 03300.

C. Provide reinforcing under the provisions of Section 03300.

## 2.12 [MANHOLE ACCESSORIES]{.underline}

A. Manhole Frames and Covers: ASTM A48; Class 30B gray cast iron,
machine finished with flat bearing surfaces. Covers shall be round and
have \"Electric\" or \"Signal\" as designated on plans and \"SNLA\" in
permanent lettering.

B. Sump Covers: ASTM A48; Class 30B gray cast iron.

C. Pulling Irons: 7/8 inch diameter steel bar forming a triangle of 9
inches per side when set. Galvanize to ANSI/ASTM A153 for irregular
shaped articles. Locate opposite each duct entry.

D. Cable Rack Inserts: Steel channel insert with minimum load rating of
800 pounds, length to match cable rack channel. Locate 3\' on center.

E. Cable Rack Channel: 1-1/2 x 3/4 inch steel channel wall bracket, 48
inch length, with cable rack arm mounting slots on 1-1/2 inch centers.

F. Cable Racks: ANSI/ASTM A569; steel channel, 1-1/2 x 3/4 x 14 inches
with fiberglass reinforced polyester or porcelain cable supports and
fastener to match mounting channel.

G. Manhole Ladder: Cast iron, suitable for manhole shape and
construction. Primed and painted light grey.

H. Waterproofing: Exterior coating of manholes shall be required. The
coating shall be a waterproofing type bitumastic or asphaltic material
such as Koppers 300M or approved equal.

I. Ground Rods: 3/4\" x 10\' Copperweld.

J. Grade Rings: Pre-cast concrete (4000 psi. minimum compressive
strength at 28 days) with inside diameter equivalent to manhole opening
specified in Section 2.10H. The ring shall have circumferental rebar #3
minimum with a trowel finish to provide a true plane within 1/8 inch, as
determined with a 5-ft straight edge.

# PART 3 - EXECUTION

## 3.01 [CONDUITS - GENERAL]{.underline}

A. The entire trench between terminal points of the conduit run shall be
opened before any conduit is laid in order to determine if any
obstructions exist. Install duct to locate top of ductbank at depths as
indicated on drawings. Any existing utility line crossings are to be as
built on drawings showing: type of line, size, and depth below the
surface.

B. Duct banks shall have conduit joints staggered at least six inches,
both vertically and horizontally.

C. Spacers shall be used where more than one duct is installed and shall
be the standard product of the duct manufacturer for the type and size
duct. They shall be located at five foot intervals, secured to the ducts
with #16 gage iron wire. The spacers shall be securely anchored to the
bottom of the trench to prevent ducts from floating during concrete
pouring. Unless otherwise noted on drawings, 4\" conduit shall have an
approximately 7.5 inch spacing center-to-center, both horizontally and
vertically; 5\" conduit shall have an approximate 8.56 inch spacing
center-to-center.

D. Continuous spading during pouring shall be performed to ensure a flow
of concrete between and under ducts to eliminate voids. Mechanical
vibrators shall not be used.

E. Terminate conduits in an end bell at manhole and building foundation
penetrations. Stub-ups of rigid or IMC duct in equipment pads shall have
insulated grounding bushings.

F. Apply corrosion protection tape, half lapped, to non-PVC-coated
underground metallic conduit and fittings that are in direct contact
with earth only.

G. Conduit and duct runs shall be short, straight runs between points of
the system. Bends shall be laid out with the greatest possible radius.

H. Duct runs shall be graded to drain toward one or both terminal points
of the duct run. The slope shall not be less than 2 inches for every 100
ft. of length, unless otherwise shown on contract drawings.

I. Conduits and duct runs shall be installed on compacted soil when
entering a manhole, building foundation, crossing a road, railroad
track, or bridge abutment to prevent shear stress on the conduit.

J. All paving and concrete cuts shall be made with a concrete saw. All
surfaces to be replaced shall match existing and shall be in accordance
with applicable concrete of asphalt specifications.

K. Conduit penetrations into buildings or through above ground
foundations, shall be sealed with duct seal or conduit sealer to prevent
gas or water entry.

L. Trenching and backfilling shall be in accordance with Specification
02200 - Earthwork.

M. Wires, cables, or other conductors shall be pulled into the duct as
shown on the drawings. Empty ducts shall have a 1/4\" polypropylene rope
provided with 2 feet of slack at each end with both ends secured.

N. When multiple channel innerducts (FO-DUCT) are pulled through
conduit, secure every 10-ft section so as to prevent rolling of channels
within conduit. Leave one-foot ends protruding from face of manhole.

O. Conduit or duct banks shall maintain 1 foot vertical and 1 foot
horizontal separation from other utility lines where possible. A
separation of 6 feet is desired from steam lines, except at a crossing
where power duct shall cross under the steam line with a minimum of 1
foot vertical separation.

P. A warning tape shall be installed one foot above duct. The warning
tape shall be of inert plastic film 4 mils thick specifically formulated
for prolonged use underground, resistant to alkalis and acids found in
soil. It shall have a tensile strength of 30 pounds per 3 inch wide
strip. The tape shall bear a continuous printed message repeated every
36 inches. The tape shall be Terra Tape Standard 250 manufactured by
Reef Industries, Inc., or approved equal. The tape shall be colored in
accordance with American Public Works Association (APWA) recommended
color code for marking buried lines of all types. Current recommended
colors are Red for power lines and Orange for telephone/signal.

Q. Where above grade marking of underground utilities is indicated on
drawings, the marking shall be in accordance with Standard Electrical
Drawing 92310.

R. Swab Duct: use suitable caps to protect installed duct against
entrance of dirt and moisture.

## 3.02 [CONCRETE ENCASED CONDUITS]{.underline}

A. Provide minimum four inch concrete cover at bottom, top, and sides of
conduit or duct bank.

B. A mandrel 1/4\" - 3/8\" smaller than the conduit shall be pulled
through each conduit. A circular wire brush the same diameter of the
conduit shall be pulled through the conduit.

C. Conduit stub outs shall be RGS or IMC capped and not encased in
concrete for future accessibility. Capping shall prevent moisture or
debris from entering the duct system.

## 3.03 [DIRECT BURIED CABLE - GENERAL]{.underline}

A. The cable shall be reeled from the cable reel to trench avoiding
dragging it over the surface of the ground. The cable shall not be under
tension after installed in the trench.

B. Bedding material as specified in 2.08B shall be used as backfill to
cover the cable a uniform depth of 4\".

C. The remaining trench shall be backfilled screening out sharp rocks
and other debris so as to avoid damage to the cable. Backfilling and
tamping shall be in accordance with the Specification on Excavation,
Fill, Backfill, and Trenching.

D. A plastic warning tape shall be installed one foot above the cable
the complete length of the trench. For power, the tape shall be Red in
color with black lettering \"Warning Buried Electric Lines\" Terra Tape
or equivalent. For telephone or signal, the tape shall be Orange in
color with black lettering \"Warning Buried Signal Lines\" Terra Tape or
equivalent.

## 3.04 [MANHOLES - PRECAST CONCRETE]{.underline}

A. Excavate, install base material, and compact base material. Compact
to 95% density or as required by manufacturer.

B. Install, seal, and waterproof precast sections in accordance with
manufacturer\'s instructions.

C. Use precast grade ring sections to bring manhole entrance to proper
elevation.

D. Install manholes plumb.

E. Set the top of each manhole to finished elevation.

## 3.05 [MANHOLES - CAST-IN-PLACE CONCRETE]{.underline}

A. Form cast-in-place manholes, inside and outside surfaces, in
accordance with provisions of Section 03300.

B. Manhole Shape: As indicated on drawings.

C. Inside Dimensions: As indicated on drawings.

D. Wall Thickness: As indicated on drawings.

E. Form window for duct entry as indicated on plans.

F. Include 12 inch drain opening and two 1-inch ground rod openings in
base section.

G. Cast cable pulling irons in place opposite each duct entry window.

H. Cast inserts for cable racks in place at three ft. centers.

## 3.06 [MANHOLE ACCESSORIES]{.underline}

A. Where manhole drainage is into sewers, suitable traps shall be
provided to prevent entrance of sewer gas into manholes and duct
systems.

B. Install 2 ground rods with top protruding 4 inches above manhole
floor. Connect ground rods with 4/0 bare copper run around perimeter of
inside manhole at floor. Copper conductor connection to ground rod to be
exothermic.

C. Waterproof exterior surfaces, joints, and interruptions of manholes
after concrete has cured 28 days minimum.

D. Attach cable racks to inserts after manhole construction is complete.

END OF SECTION