July 22, 1994

Contract #TW0592

SPECIAL SPECIFICATION

SECTION 02685-S

[EXTERIOR GAS PIPING SYSTEMS]{.underline}

Page

[PART 1 - GENERAL]{.underline}

1.01 Description Of Work 2

1.02 Quality Assurance 2

PART 2 - PRODUCTS

2.01 Pipe 2

2.02 Pipe Fittings 3

PART 3 - EXECUTION

3.01 Pipe 4

3.02 Joining Of Polyethylene Plastic Pipe 5

3.03 Material Handling And Defects 9

3.04 Test Requirements 9

SPECIAL SPECIFICATION

SECTION 02685-S

[EXTERIOR GAS PIPING SYSTEMS]{.underline}

# PART 1 - GENERAL

## 1.01 [DESCRIPTION OF WORK]{.underline}

A. [This section]{.underline} shall apply to the materials and
operations required for the installation of underground exterior gas
distribution systems, including all piping, fittings, installation,
joints, location devices, service risers, and tests.

B. [Related Sections]{.underline}: Refer to Division 2, Section
\"Earthwork\" for related work.

## 1.02 [QUALITY ASSURANCE]{.underline}

> [The materials and practices]{.underline} comprising the work shall
> conform to this and other referenced standard specifications. Where
> this specification conflicts with the requirements of another
> referenced specification, this specification shall prevail.

# PART 2 - PRODUCTS

## 2.01 [PIPE]{.underline}

> [The underground gas distribution system]{.underline} shall be all
> polyethylene plastic pipe PE 3406, or PE 3408, SDR 11 IPS, (Phillips
> Products Co., Inc. \"Driscopipe 8000\" or approved equal) unless
> otherwise specified on the contract drawings. The polyethylene plastic
> pipe used shall conform with the latest ASTM D 2513, publication of
> specifications for thermoplastic gas pressure pipe, tubing, fittings
> and the following ASTM minimum test requirements:

[Property]{.underline} [ASTM Test]{.underline}

Density, gms/cc D 1505

Melt Flow (Condition F) gms/10 min. D 1238

Environmental Stress Cracking

Resistance (Condition C) Hrs. D 1693

Tensile Strength, Ultimate

psi 2 in./min. D 638

Tensile Strength, Yield

psi 2 in./min. D 638

Elongation, %, 2 in./min. D 638

Impact Strength, ft. lbs./in. notch

Specimen thickness 0.250 in.

0.125 in. D 256

Vicat Softening Temperature

deg. F. D 1525

Brittleness Temperature, deg. F. D 746

Flexural Modulus, psi D 3350

Modulus of Elasticity, psi D 638

Hardness, Shore D D 2240

Coefficient of Linear

Thermal Expansion in./in./deg. F.

Molded Test Specimen Extruded Pipe D 696

Long-Term Strength, psi @ 73.4 deg. F. D 2837

Cell Classification D 3350

PPI Material Destination PE 3406

PE 3408

## 2.02 [PIPE FITTINGS]{.underline}

A. Heat fusion fittings shall conform to ASTM D 2513 and be installed in
accordance with article 3.01 of this specification and the
manufacturer\'s recommendations.

B. [Mechanical joint fittings]{.underline} shall conform to ASTM D 2513
and be installed as per manufacturer\'s recommendations.

C. [Valves]{.underline}

1\. Valves shall be Class 150 ANSI butt weld, one-quarter turn Xonox
"Tufline" Model 166 BW Natural gas valve.

2\. Valves shall be connected to piping with a transition fitting having
a double \"O\"-ring seal.

D. [Valve Boxes]{.underline}: Valve boxes shall be installed where
indicated and as detailed on the contract drawings. Valve boxes shall be
extension type, cast-iron boxes with drop covers containing the \"GAS\"
in the cover, and shall be TYLER Roadway Boxes No. 1400 or equal.

# PART 3 - EXECUTION

## 3.01 [PIPE]{.underline}

> [Plastic pipe]{.underline} shall be installed a minimum of 48\" deep
> and shall be handled with care as it is lowered into the ditch. Pipe
> shall not be subjected to unnecessary strains such as bending or
> twisting at any time. The pipe shall be laid on the ditch bottom in
> such a manner as to snake the pipe from one side of the ditch to the
> other with one cycle approximately every 40 feet. The pipe shall be
> laid and continuously supported on undisturbed or well-compacted soil.

A. [Underground Clearance]{.underline}: Each distribution line shall be
installed with at least 12\" of clearance from any other underground
structure not associated with the distribution line. In addition, all
plastic pipe and plastic service lines shall be installed with
sufficient clearance, or shall be insulated, from any source of heat so
as to prevent the heat from impairing the serviceability of the pipe.

B. [Bends]{.underline}: The pipe may be bent or deflected a maximum
amount equal to 1.33 times the minimum radius recommended by the
manufacturer. Bends shall be free of buckles, cracks, or other evidence
of damage. Changes in direction which cannot be made by bends shall be
made with elbow or tee fittings. Elbow or tee fittings shall not be
trimmed to fit. Miter joints are not permitted.

C. [Obstructions in the Pipe]{.underline}: The open ends of the pipeline
shall be closed at the end of each day\'s work, and shall not be
reopened until such time as the next joint of pipe is to be connected.
This closure shall be capable of preventing the entrance of small
animals or the introduction of foreign material (water included) of any
nature into the line. Care shall be exercised when joining the sections
of pipe to minimize the possibilities of any foreign material being in
the line after its completion. Any obstructions in the pipeline caused
by foreign material shall be removed by the Contractor.

1\. If the pipe contains dirt, sand or other foreign materials after it
has been strung along the right-of-way, each length shall be swabbed
prior to welding it into the pipeline. The swab shall be a soft cloth.
Each length shall be visually inspected internally prior to use.

2\. After the pipeline, or measured portions thereof, is complete, the
Contractor shall run a polyurethane pipeline pig through the line twice.
Prior to the pigging operations, a pig catcher shall be installed to the
end of the pipeline in a manner which will prevent the pig from blowing
off during the operation. The pigging operation shall provide for the
controlled running of the pig. The pig shall be moved by air pressure
only. The use of gas pressure in the pigging operation is prohibited.

D. [Backfill]{.underline}: In warm weather, backfilling shall be
performed during the coolest part of the day whenever possible. Backfill
material shall be soft dirt or sand free of stones or debris that may
cut or otherwise damage the pipe. Clean backfill material shall surround
the pipe for at least 4\" in all directions. Backfill shall be placed
level from one wall of the ditch to the other and shall not be mounded
over the pipe.

> Tamping shall be performed by placing backfill in maximum of 8\" lifts
> and compacting with the proper equipment. The pipe shall not be
> damaged during compaction. When flooding of the ditch is used to
> consolidate backfill, the pipe shall not be allowed to float from its
> bearing on the ditch bottom. Compaction with heavy equipment is not
> permitted unless the pipe has 24\" of cover and the pipe internal
> pressure exceeds 15 psig.

E. [Location Device]{.underline}: An electrically conductive 12 gauge
copper wire shall be installed with the pipe. This wire and all its
underground connections shall be insulated to prevent corrosion. This
wire shall be placed above the pipe with a 12\" layer of backfill
separating it from the top of the pipe. A detectable warning tape shall
be placed 6\" above the 12 gauge wire. The warning tape shall then be
covered with 18\" of backfill minimum and additional detectable warning
tape shall be placed a minimum of 12\" below finished grade. Detectable
warning tape shall have a minimum foil core thickness of 0.5 mils and
shall be reinforced consisting of 9.0 mil total thickness. Warning tape
for gas lines shall be 6\" wide. (Minimum pipe depth is 48\".)

F. [Tie-in to Other Lines]{.underline}: After lowering the pipe into the
ditch and prior to joining installed sections or making tie-ins to other
lines, sufficient time shall be allowed for contraction as the pipe
assumes ground temperature. Tie-ins to existing lines shall be performed
in an atmosphere absent of gas. Hot tie-ins are not permitted.

## 3.02 [JOINING OF POLYETHYLENE PLASTIC PIPE]{.underline}

A. [General]{.underline}: The Contractor\'s personnel who perform
heat-fusion joining on distribution facilities shall be qualified by the
pipe manufacturer\'s qualifying representative in accordance with
article 3.02 E prior to starting any work. The Contractor may, at his
option, submit a list of previously qualified candidates to the Sandia
Delegated Representative (SDR) in lieu of retesting. The list shall
include the date of qualification, and the name of the SDR that was
present for the test.

> No heat-fusion joining shall be performed when the quality of the
> joining may be adversely affected by weather conditions. Rain, blowing
> sand, wind storms, and other inclement weather shall be cause for the
> SDR to cease welding operations. Wind shields may be used during windy
> weather if approved by the SDR.

B. [Heat-Fusion Joints]{.underline}: Heat-fusion joints are made by
heating the mating surfaces to their fusion temperature, compressing the
mating surfaces together, and holding the mating surfaces together until
the joint cools naturally. Direct application of heat using a torch or
other open flame is prohibited.

> Equipment and tools which are manufactured specifically for the fusion
> process shall be used. The equipment shall be designed to hold the
> heating element firmly against and parallel to the mating surfaces,
> compress the heated surfaces together and hold the surfaces firmly
> together in alignment until the joint cools naturally. The heating
> elements shall be the electric type which are thermostatically
> controlled. The heating tools shall be capable of maintaining uniform
> surface temperature within the melt-temperature range specified by the
> material manufacturer. A crayon temperature indicator shall be used by
> the Contractor to verify that the heating element temperature is
> correct prior to making each joint. The temperature crayon mark shall
> not be applied to the part of the heater face that comes in direct
> contact with the pipe.

C. [Procedure (Butt-Fusion)]{.underline}: The following procedure shall
be used when joining pipe, elbows, tees, caps, reducers, and transition
fittings:

1\. Place pipe ends into alignment equipment. Square the end of each
pipe section to be joined using the facing tool of the fusion machine.
Remove cuttings and burrs from the pipe ends. Wipe each pipe end to
remove dirt, water, grease, and other foreign material.

2\. Place pipe ends together and carefully check alignment of the pipe
to ensure that the pipe ends meet squarely and completely over the
entire surface to be joined. If they do not meet squarely and
completely, reface and recheck.

3\. Insert the hot heating tool between the aligned pipe ends. Push the
ends to be joined simultaneously against the heating tool with
sufficient force to insure contact only. Hold in place until a bead of
molten plastic rolls back from the heated ends. The bead shall be
approximately l/l6\" in size. During this step, the temperature of the
heating tool shall be maintained at the temperature specified by the
material manufacturer.

4\. Move the pipe ends away from the heating tool, remove the tool and
bring the heated ends together immediately with firm pressure to form a
uniform upset flash about 1/8\" to 3/16\" wide around the entire
circumference of the pipe. Maintain this pressure for approximately 15
seconds. (If the pipe ends are pushed together with too much force, all
molten material will be pushed out of the joint and cold material will
make contact.) If the softened material sticks to the heating tool, the
SDR shall require the Contractor to discontinue the joint, clean the
heating tool and start over with Step 3.02 C.l.

5\. Allow the joint to cool and solidify until the bead feels hard
before removing the clamps or other aligning device. The joint shall not
be subjected to external stresses until after cooling in ambient air for
5 minutes. Internal pressure shall not be applied until the joint and
surrounding material has reached ambient temperature. If the butt joint
is not satisfactorily completed, cut out the joint and start over with
Step 3.02 C.l.

D. [Procedure (Sidewall Fusion)]{.underline}: The following procedure
shall be used when joining service tees and saddles to pipe:

1\. The pipe shall be round and uniform in the area of fusion. If
necessary, cold ring clamps shall be placed on each side of the fusion
area.

2\. Remove the glossy coating of the pipe surface and the saddle face
using emery cloth. Place saddle against pipe surface and check to see
that the surfaces to be joined fit along the circumference of the pipe.
If they do not fit, move to another location on the pipe surface and
start over.

3\. Insert the saddle heating tool between the pipe surface and the
saddle face. Push the surfaces to be joined simultaneously against the
heating tool applying a strong firm continuous pressure. Hold this
pressure until a completed melt bead can be seen on the pipe. Release
strong pressure to a light pressure and continue the heat cycle until a
melt bead of approximately l/8\" to 3/16\" in size appears on the base
of the fitting. During this step, the temperature of the heating tool
shall be maintained at the temperature specified by the material
manufacturer.

4\. Remove saddle from heating tool and heating tool from the pipe
surface. Inspect both heated areas for uniformity and for sufficient
melt. If either melt pattern appears faulty, repeat Step 3.02 D.3. Bring
melted surfaces together rapidly without slamming and apply continuous
progressive pressure until proper bead is formed.

5\. Allow the joint to cool and solidify until the bead feels hard. The
joint shall not be subjected to external stresses until cooling 10
minutes in ambient temperature.

> If for any reason the saddle joint is not satisfactorily completed,
> the section where the melt occurred shall be cut out and replaced with
> a new section.

E. [Heat-Fusion Joining Qualifications]{.underline}:

1\. [Heat-Fusion]{.underline}: Heat-fusion joining shall be performed by
persons who are familiar with the material manufacturer\'s recommended
procedures and shall be qualified in accordance with the following
applicable procedure(s).

2\. [Butt Fusion]{.underline}:

a\. Candidates for qualifications as butt-fusion joiner shall make the
number of joints shown in the table below:

[Pipe Size]{.underline} [Number of Joints]{.underline}

5/8\" Tubing 3

l-l/4\" - 2\" Tubing 3

4\" Pipe 3

> For ease in testing, the joints made shall be fabricated into the
> following test samples:

[Pipe Size]{.underline} [Configuration]{.underline}

1-1/4\" - 4\" Pipe A cap fused to a 24\" section of pipe. The 24\"
section of pipe fused in a 12\" section of pipe. A cap fused to the 12\"
section of pipe.

5/8\" Tubing A service tee fused to the 24\" section of pipe. A 24\"
section of tubing fused on the service tee. A transition fitting fused
to the 24\" section of tubing.

3\. Qualifying joints shall be made under field condition in the
presence of the pipe manufacturer\'s qualifying representative and the
SDR without any assistance or advice.

4\. Upon completion of the heat-fusion joining process, the test
sample(s) shall be allowed to remain undisturbed until the entire
assembly has cooled to ambient temperature. Then the following physical
test shall be imposed on the joints:

a\. Each assembly shall be subjected to a 150 psig air test for at least
2 hours.

b\. Upon completion of the pressure test, one joint shall be selected
from each diameter assembly for further testing. The selection shall be
such that each joint represents the joining of different components;
example, one joint can be pipe to pipe, another joint can be pipe to
cap. Selection from the service assembly may be either between the
tubing and transition fitting, or between the tubing and service tee.

c\. The selected joints shall be removed from the assembly by cutting
the pipe not more than 2\" away from the joint. Each joint removed shall
be cut axially to split the joint into 90 degree sections. These
sections shall be trimmed circumferentially to a strip 1\" in width. The
5/8\" joint need not be trimmed.

d\. The bonding strength of this joint shall then be tested by folding
each strip at the joint and flattening it in a vise or other compression
device. Each strip shall be folded and flattened in each direction.
Separation at the joint will be considered failure.

5\. The qualification test will be deemed successful and the candidate
will be considered qualified if none of the heat-fusion joints fail any
of the tests. If unsuccessful, the candidate may be allowed to repeat
the test immediately, provided no more than one joint is found to be
faulty. If more than one heat-fusion fails, further training will be
required before the candidate can repeat the test.

a\. Upon completion of the test, the Contractor shall submit a list of
qualified candidates to the SDR for permanent record.

b\. Marking of Joints: Each person performing heat-fusion joining on a
pipeline shall have a distinctive mark which shall be placed on the pipe
with a felt-tip pen near each heat-fusion joint completed. The mark
shall be that appearing on the Welder\'s Qualification Card. The color
of the pen shall be such that the mark is distinguishable from the color
of the pipe.

6\. [Transition Fittings]{.underline}: Plastic-to-steel connections
shall be made with a transition fitting specifically made for that
purpose. The fitting shall be designed to be butt-fused on the plastic
end and welded on the steel end.

7\. [Cutting]{.underline}: When it is necessary to cut the pipe, it
shall be cut with special plastic pipe cutters, with a fine-toothed
handsaw, or a hacksaw. The pipe ends shall subsequently be faced in
order to obtain a clean, square end free of burrs for joining.

8\. [Heat-fusion joints]{.underline} (made by a trained and qualified
technician): The SDR may select joints to be tested by destruction or by
ultrasonic methods. Destructive tests shall be made by removal of the
joint to be tested and replacing the removed section of pipe with a
\"pup\" joint at least 3 feet long. Test specimens shall be cut and
tested in accordance with article 3.02 E.

> Heat-fusion joints tested by ultrasonic methods shall be free of voids
> or any imperfection which would impair the serviceability of the
> joint.

## 3.03 [MATERIAL HANDLING AND DEFECTS]{.underline}

A. [When loading or unloading plastic pipe]{.underline}, the pipe shall
be placed into the desired position without damage. The pipe shall not
be allowed to drop freely from the truck bed to the ground. The pipe
shall be strung onto terrain free from rocks or other projections which
might cause damage to the pipe. The pipe shall not be dragged over rocks
or other abrasive material.

> Plastic pipe shall be protected from fire, excessive heat, or harmful
> chemicals. Cleaning solutions, detergents, solvents, alcohols, etc.,
> shall not be allowed to contact the pipe.

B. [Inspection of Materials]{.underline}: The Contractor shall visually
inspect each length of pipe and all components, both inside and out, at
the site of installation to insure that it has not sustained damage that
could impair its serviceability. A second surface inspection shall be
made immediately prior to lowering the pipe into the ditch.

C. [Damage, Defects and Repairs]{.underline}: Any pipe which has cuts,
gouges, scratches, punctures or other damage or defects that would
impair the serviceability of the pipe shall be repaired by removal of
the defective section and replacement by a new section of pipe.

## 3.04 [TEST REQUIREMENTS]{.underline}

A. [All new segments of line]{.underline} shall be tested by the
Contractor in accordance with the following procedure or an acceptable
procedure submitted in writing by the Contractor and approved by the
SDR. The SDR shall be notified prior to the start of each test.

B. [Test Procedure]{.underline}:

1\. Air shall be the test media. The air used in testing shall be free
of contaminants.

2\. The temperature of the plastic material shall not exceed 100 deg F
due to the temperature of the compressed air or any other source.

3\. The minimum test pressure shall be 1.5 times the maximum operating
pressure, or 90 psig, whichever is greater.

4\. Tie-in joints which are not included in the test shall be
soap-tested at the operating pressure. After the soap test, all of the
soap shall be removed from the pipe by a thorough washing with water.

5\. Polyethylene pipe and tubing shall not be used as vent lines in
testing or purging operations.

C. Test Duration: The pressure shall be maintained at or above the
minimum test pressure for the periods shown in the following tables.
Time shall begin when the pressure in the system has stabilized. Any
leakage in the line shall be cause for failure of the test. If the test
is failed, the Contractor shall repair the defective line and retest at
no additional cost to Sandia National Laboratories (SNL).

[2\" Pipe or Less]{.underline}

[Length]{.underline} [Time in Hours]{.underline}

100 feet or less 1

101 feet to 500 feet 2

501 feet to 2,000 feet 3

2,001 feet to 10,000 feet 4

over 10,000 feet 12

[4\" Pipe or Greater]{.underline}

[Length]{.underline} [Time in Hours]{.underline}

100 feet or less 1

101 feet to 500 feet 2

501 feet to 2,000 feet 3

2,001 feet to 10,000 feet 12

over 10,000 feet 16

D. [Compensation for Change in Temperature]{.underline}: The temperature
shall be monitored throughout the test duration. Losses due to change in
temperature shall be calculated with the following equation:

New Pressure = Old Pressure x [New Temperature + 460]{.underline}

Old Temperature + 460

E. [Method of Test]{.underline}: A recording gauge shall be used on all
tests of facilities which will operate at 100 psig or more.

F. [Safety During Test]{.underline}: Every reasonable precaution shall
be taken to protect workers and the general public during testing. No
direct connections will be permitted from the new line to any existing
gas lines unless they are physically separated. Suitable steps shall be
taken to keep persons not involved in the test procedure out of the
testing area during the test.

G. Test Records: A record of each test shall be prepared as part of the
test procedure. The record must contain the following information:

1\. Company name.

2\. Name of person responsible for the test (directly).

3\. Copy of qualifications of person responsible.

4\. Test fluid used.

5\. Test pressure.

6\. Test duration.

7\. Leaks and failures noted and their disposition.

8\. Name of the SDR accepting the test.

> This record shall be submitted to the SDR.

END OF SECTION