2020 Standards and Specifications for Water Wastewater Construction

A continuous #12 Gauge coated copper tracer wire shall be installed with all non-metallic
pipe including service lines from the main to the meter box. The location of the tracer
wire for PVC water and Force Main pipe(s) shall be 6 inches above the pipe in the trench
and not touching the main at any point. All tracer wires shall be looped with service lines
to water meter boxes and Force Main lateral kit boxes. The wire shall be looped around
valves, saddles, curb stops and other appurtenances in a manner that ensures no
interference with the operation of the appurtenances. The tracing wire shall be terminated
in valve boxes, extending to the top inside of the box for easy connection.

Pipe Deflection. During the pipe laying operation, deflections at joints shall not exceed
the amounts indicated in the following tables for the various types of joints and pipe or as
recommended by the manufacturer.

(1) Mechanical joint pipe (Iron Pipe)

Size of Pipe Degrees
4”-6”-8”-12”
16”-20”-24”-30” 5o
2o
36”-42”-48” 2o

(2) Push-on joint pipe (Iron Pipe)

Size of Pipe Degrees
4”-6”-8”-12” 5o
3o
16”-20”-24”-
30”-36” 2o

42”-48”

(3) PVC pipe The deflection shall not exceed the maximum deflection
recommended by the pipe manufacturer(s).

Encasement Pipe. Installation of pipe in encasement structures shall be accomplished in
a manner that ensures neither is damaged. Care must be exercised to ensure that the
joints of the pipe are not deflected beyond approved deflection or pulled out during the
process. The pipe shall be jointed and pulled or jacked through the encasement structure.
Cables, chains, jacks or other equipment and/or devices used shall not be in direct contact
with the pipe unless thoroughly padded.

Casing spacers shall be provided to provide stability during installation and after the pipe
is in place. If, after installation of the pipe, adequate stability has not been provided, in the
opinion of the Engineer, the pipe shall be removed and reinstalled. Spacer material(s) will
be either plastic or stainless steel dependent upon application. Utility will determine
application during project review.

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10. Jointing Mechanical Joint Pipe & Fittings.

Wipe clean both the socket and plain end. Lubrication and additional cleaning should be
provided by brushing both the gasket and plain end with an approved pipe lubricant prior
to slipping the gasket onto the plain end for joint assembly. Place the gland on the plain
end with the lip extension toward the plain end, followed by the gasket with the narrow
edge of the gasket toward the plain end.

Insert the pipe into the socket and press the gasket firmly and evenly into the gasket
recess. Keep the joint straight during assembly.

Push the gland toward the socket and center it on the pipe with the gland lip against the
gasket. Insert bolts and hand tighten nuts. Establish desired deflection after joint
assembly but prior to tightening bolts.

Cutting pipe for insertion of valves, fittings or closure pieces shall be done in accordance
with all safety recommendations of the manufacturer(s) of the cutting equipment. Cutting
shall be accomplished in a safe, craftsman like manner without creating damage to the
pipe or cement-mortar lining.

Existing gray-iron pipe may be cut using a hydraulic squeeze cutter or abrasive pipe saw.

Ductile-iron pipe shall be cut using an abrasive pipe saw only.

Cut ends and rough edges shall be ground smooth, for push-on joint connections the cut
end shall be beveled by methods recommended by the manufacturer(s).

Joints shall be tightened by advancing the nuts with a wrench 180o apart until a tight joint
is achieved.

The Contractor shall provide a "torque wrench" suitable for measuring tension on bolts
for at least such time as the work group making the joints have obtained the "feel" of the
required tension. At no time should handles longer than those supplied by the wrench
manufacturer(s) be permitted. The torque range shall be as follows or as recommended
by the manufacturer:

5/8" Bolts 40 - 60 ft. Lbs.
3/4" Bolts 75 - 90 ft. Lbs.

1" Bolts 100 - 120 ft. Lbs.
1 1/4" Bolts 120 - 150 ft. Lbs.

After the work group has become accustomed to this torque, a socket wrench with a 10”
handle may be used.

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The rubber gasket and joint bolts of mechanical joint retainer glands shall be installed in
accordance with the above requirements. Set screws shall be tightened evenly to
approximately 75-foot pounds.

11. Jointing Push-On Joint Pipe.

Thoroughly clean the groove and bell socket of the pipe or fitting; also clean the plain end
of the mating pipe. Using a gasket of the proper design for the joint to be assembled,
make a small loop in the gasket and insert it in the socket, ensuring the gasket faces the
correct direction and that it is properly seated. In cold weather, it is necessary to warm
the gasket to facilitate insertion.

Apply lubricant to the gasket and plain end of the pipe in accordance with the pipe
manufacturer'(s) recommendations. Lubricant is furnished in sterile cans and every effort
should be made to maintain the sterile environment. It is important to follow the pipe
manufacturer(s) instructions.

Ensure the plain end is beveled; square or sharp edges may damage or dislodge the
gasket and result in a leak. When pipe is cut in the field, bevel the plain end with a heavy
file or grinder to remove all sharp edges. Push the plain end into the bell socket of the
mating pipe. Keep the pipe joint straight while pushing. Establish deflection after the joint
is assembled. Small pipe can be pushed into the bell socket with a long bar. Large pipe
requires additional power, such as a jack, lever puller or perhaps a backhoe. A timber
header should be used between the pipe and the jack or backhoe bucket to avoid damage
to the pipe.

12. Jointing Flanged Pipe & Fittings.

The faces of all flanges shall be thoroughly cleaned and all burrs or imperfections
removed and brushed with a steel brush.

Gaskets between flanges shall be rubber of 1/16” minimum thickness.

Care shall be taken to prevent strain to the flanges. All bolts and nuts shall be cleaned
and lubricated prior to tightening. Bolts on opposite sides shall be tightened alternately
to the torque listed in Section #20.

13. Jointing PVC Pipe.

Both bell and plain end of pipe shall be thoroughly cleaned prior to attempting to join the
pipe. Place rubber gasket in bell (if not delivered from supplier in place). The colored
side of gasket shall be to the outside.

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Lubricate the plain end (do not lubricate the bell end) with approved lubricant and insert
plain end into bell until stop mark on plain end is flush with the end of the bell. In a situation
where the pipe has two marks on the plain end, insert plain end into bell so that only one
mark is visible.

Once the pipe is cut, plain ends must be beveled similar to the bevel on full lengths. After
beveling, stop marks must be applied to the ends. Use the plain end of another piece of
pipe or fitting to determine the location of the stop mark, then mark the piece of pipe that
has been cut. The joints shall be inserted as far as possible on each side of any valves
that are inserted in the line.

14. Installation of Valves.

Valves. Prior to installation, valves shall be inspected for direction of opening, number of
turns to open, freedom of operation, tightness of pressure-containing bolting and test
plugs, cleanliness of valve ports and especially seating surfaces, handling damage and
cracks. Valves shall be closed before being installed.

Valves, fittings, plugs and caps shall be set and joined to the pipe in the manner specified
for cleaning, laying and joining pipe, except that 12” and larger valves should be provided
with special support such as crushed stone or concrete pads to ensure the pipe will not
be utilized to support the weight of the valve.

A valve box shall be provided for each valve that has no gear or operating mechanism or
in which the gear or operating mechanism is fully protected with a gear case. The valve
box shall not transmit shock or stress to the valve. The valve box shall be centered and
set plumb over the operating nut of the valve, the box cover flush with the surface of the
finished areas or such other level as may be directed by the Engineer.

When the distance between the valve operating nut and the finished surface exceeds 5',
a valve stem extension shall be provided. The stem shall be round steel bar stock or steel
pipe of the dimensions shown below with a 2” square bar steel operating nut (except on
2” valve(s) attached to the upper end. The stem extension shall be of adequate length
to reach from the valve operating nut to a point within 12” to 18” of the finished surface.
A box wrench, 2 1/8" I.D. square, made from steel 3/16” thick shall be welded to the lower
end of the stem extension which will fit over the valve operating nut.* A round center
guide made from 3/16” or ¼” steel plate shall be placed on the valve stem extension
approximately 6” from the upper end. The diameter of the guide shall be slightly less than
the inside diameter of the valve box. The guide shall be affixed to the stem extension in
such a way that it can rotate freely on the stem. A bituminous coating shall be applied to
all stem extension pieces.

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Listed below are approximate dimensions for the valve stem extensions for various size
valves:

NOTE: *Welds on stem extensions (top and bottom nut) shall be 1/8" - 3/16" fillet weld around full

circumference, small - large valve stem extension.

Stem Size Stem Size Shear Maximum

Valve Size (Steel Pipe) (Bar Stock) Pins Depth of

Bury

2"-4" (Small) 3/4" (1.13 lbs./ft) 3/4" 3/16" 10'

6"-12" (Butterfly & 7/8" 3/16" 13'
Gate Valves) 1 1/4" 3/8" 13'
4"-36" (Butterfly) 3/8" 13'
3"-16" (Gate Valves) 1" 1/2" 21'
1 1/2"
16"-36" (Butterfly) 20"
20” & Larger (Gate Valves)

42"& Larger (Butterfly)
20" & Larger (Gate Valves)

Drawings of approved stem extensions are available at the Utility office. Shop drawings
shall be submitted to the Engineer for approval prior to installing the stem extension
pieces.

Valve vault. A valve vault designed to prevent settling of the pipe shall be provided for
each valve that has exposed gear(s) or operating mechanisms. The operating nut shall
be readily accessible for operation through the opening in the valve vault which shall be
set flush with the surface of the finished pavement or such other level as may be specified.
Vaults shall be constructed to permit minor valve repairs and to protect the valve and pipe
from impact where they pass through the vault walls.

Blowoff Valves. All dead ends on new mains shall be closed with plugs or caps that are

suitably restrained to prevent separation under test pressure. If a blowoff valve precedes

the plug or cap, it too shall be restrained against blowing off. All dead ends greater than
200’ shall be equipped with suitable blowoff facilities (i.e. Mainguard No. 77 or as

otherwise specified by Utility).

15. Installation of Tapping Sleeves and Tapping Saddles.

The pipe shall be free of dirt and other debris before attaching tapping sleeve or tapping
saddle. That part of the pipe barrel, other than concrete pipe, which will be in contact with
the gasket of tapping saddles shall be smooth. All rough areas on the pipe barrel shall be
smoothed.

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Tapping saddles or sleeves shall be bolted securely to the pipe. The face of the outlet
shall be plumb. Mechanical joint glands for tapping sleeves shall be installed as described
in these specification(s). The strap bolts for tapping saddles shall be alternately tightened
"snug" and then alternately tightened to a torque of 100-foot pounds.

The tapping valve shall be bolted securely to the tapping sleeve or tapping saddle outlet
flange. The tapping machine shall be bolted securely to the valve.

After installation of the tapping sleeve or saddle and the tapping valve and before drilling
through the pipe, the assembly shall be hydrostatically tested at the pressure as
described in these specification(s) by introducing water or air through the sleeve or saddle
test tap.

The pilot drill and shell cutter shall be in good condition. The shell cutter shall be the size
required to cut the full opening specified.

Only qualified operators shall operate the tapping machine. The "coupon" shall be
withdrawn and given to the Utility. Care shall be exercised to avoid drilling or cutting the
backside of the pipe by carefully ensuring the engagement of the pilot drill and shell cutter
shaft.

Openings in the pipe barrel for tapping saddles installed on dry pipe shall be cut with a
pilot drill and shell cutter. Torch cutting is not permitted. Tapping operations must not
commence before inspection by the Utility or an authorized representative.

A thick coat of bituminous material shall be applied to the straps and bolts of saddles after
installation and cleaning or by enclosing in polyethylene material in accordance with the
applicable specification(s). Coating or poly-wrap will not be required if all metal surfaces
are stainless steel.

16. Setting Hydrants.

Prior to installation, all hydrants shall be inspected for direction of opening, nozzle
threading, operating-nut and cap-nut dimensions, cleanliness of inlet elbow, handling
damage and cracks. Defective hydrants shall be corrected or held for inspection by the
Utility.

All hydrants shall stand plumb and shall have their nozzles parallel with or at right angles
to the curb, with pumper nozzle facing the curb.

Hydrants shall be set to the established grade, with the centerline of the lowest nozzle at
least 12” above the ground or as directed by the Utility. Traffic model hydrants shall be

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installed such that the breakaway flange shall be installed not less than 2”, but not more
than 6” above established grade.

Each hydrant shall be connected to the main with a 6” branch controlled by an
independent valve. The valve shall be restrained with metal tie rods or approved alternate
devices (i.e. all thread rod) to allow shutoff when the hydrant is to be removed. The fire
hydrant lead shall be ductile iron pipe only.

When a dry-barrel hydrant with an open drain port is set in clay or other impervious soil,
a drainage pit 2’ x 2’ x 2’ shall be excavated below each hydrant. The drainage pit shall
be filled with coarse gravel or crushed stone mixed with coarse sand under and around
the elbow of the hydrant and to a level 6” above the drain port.

The bowl of each hydrant shall be well braced against a sufficient area of unexcavated
earth at the end of the trench with stone slabs or concrete thrust blocks and it shall be
tied to the valve with an offset shaped, cement-lined ductile iron connector equivalent to
Gradelock as manufactured by Assured Flow Sales.

Fire hydrants shall be located as shown on the plans or as directed by the Utility and as
approved by the City of Hot Springs Fire Department. All fire hydrants shall be solid and
swivel and the valve collar should be pre-cast and floating to allow elevation changes
during and after construction.

17. Installation of Polyethylene Protection Material.

Polyethylene material shall have a minimum thickness of 4.0 mils, either in tubing form or
in the form of flat sheet or rolls, as specified herein. Polyethylene Material shall be placed
around all mechanical joints of pipe and fittings; all valves and fire hydrants with
mechanical joint ends and all saddles, sleeves, couplings, tapping saddles and any other
appurtenances with exposed bolts.

Where specified, on the plans, ductile iron pipe and appurtenances shall be completely
encased in polyethylene tubing material. It is not the intent that the material form an
enclosure that is absolutely air or water tight, but to prevent pipe to soil contact.

Polyethylene tubing shall be applied to pipe by one of the following methods:

Method "A". Cut polyethylene tube to a length approximately 2' longer than the length of
the pipe section. Slip the tube around the pipe, centering it to provide a 1' overlap on each
adjacent pipe section and bunching it in accordion fashion lengthwise until it clears the
pipe ends. Lower the pipe into the trench and make up the pipe joint with the preceding
section of pipe. A shallow bell hole must be made at joints to facilitate installation of the
polyethylene tube. After assembling the pipe joint, take bunched polyethylene from the

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preceding length of pipe, slip it over the end of the new length of pipe and secure in place.
Then slip the end of the polyethylene from the new pipe section over the end of the first
wrap until it overlaps the joint at the end of the preceding length of pipe. Secure the
overlap in place. Take up the slack width to make a snug, but not tight, fit along the barrel
of the pipe, securing the fold at quarter points with tape.

Method "B". Cut polyethylene tube to a length approximately 1' shorter than the length of
the pipe section. Slip the tube around the pipe, centering it to provide 6" of bare pipe at
each end. Make the polyethylene snug, but not tight; secure ends. Before making up a
joint, slip a 3' length of polyethylene tube over the end of the preceding pipe section,
bunching it in accordion fashion lengthwise. After completing the joint, pull the 3' length
of polyethylene over the joint, overlapping the polyethylene previously installed on each
adjacent section of pipe by at least 1', make snug and secure each end.

Pipe-Shaped Appurtenances. Bends, reducers, offsets and other pipe-shaped
appurtenances shall be covered with polyethylene in the same manner as the pipe.

Odd-Shaped Appurtenances. Valves, tees, crosses and other odd-shaped pieces which
cannot practically be wrapped in a tube, shall be wrapped with a flat sheet or split length
of polyethylene tube. The sheet shall be passed under the appurtenances and brought
up around the body. Seams shall be made by bringing the edges together, folding over
twice and taping down. Slack width and overlaps at joints shall be installed according to
manufacturer’s recommendations. Tape polyethylene securely in place at valve stem and
other penetrations.

Openings in Tubing Material. Openings for branches, service taps, blowoffs, air valves
and similar appurtenances shall be made by making an x-shaped cut in the polyethylene
and temporarily folding the film back. After the appurtenance is installed, tape the slack
securely to the appurtenance and repair the cut, as well as any other damaged areas in
the polyethylene with tape.

Junctions Between Wrapped and Unwrapped Pipe. Where polyethylene wrapped pipe
joins a pipe which is not wrapped, extend the polyethylene tube to cover the unwrapped
pipe a distance of at least 2' and secure the end.

The polyethylene material shall be secured around the pipe and appurtenances by at
least three each circumferential wraps of tape as described in these specification(s).

All tongs, cables or chains that are used for lifting pipe and appurtenances that have been
encased in polyethylene material shall be adequately padded to prevent damage to the
material.

Repair any rips, punctures or other damage to the polyethylene with tape or with a short

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length of polyethylene tube cut open, wrapped around the pipe and secured in place.

Polyethylene material shall be stored on the job site in such manner that it is not exposed
to direct sunlight. Exposure during installation shall not exceed 48 hours.

Backfill material shall be the same as specified for pipe without polyethylene wrapping.
Special care shall be taken to prevent damage to the polyethylene wrapping when placing
backfill.

18. Tunneling, Boring & Installation of Encasement Structures.

The Contractor shall inspect the location where encasement structures are to be installed
and familiarize themselves with the conditions under which the work will be performed
and with all necessary details to ensure the orderly prosecution of the work. The omission
of any detail(s) in the Plans and Specification(s) for the satisfactory installation of the work
in its entirety, which may not appear herein, shall not relieve the Contractor of full
responsibility.

The Contractor shall satisfy themselves of soil conditions by means they deem
appropriate, i.e., exploratory boring or exploratory pit excavations at tunnel ends. All such
exploratory work shall be done in a manner that will not jeopardize highway or railroad fill
and shall be satisfactorily backfilled and cleaned up.

The size structure, as shown on the plans, is considered as the "minimum acceptable
size." If the Contractor deems that it would be to their advantage to install a larger
structure, they may do so subject to approval of the Utility. Should the Contractor elect to
use larger structures, the unit bid price as stated in the Bid for the size structure specified
will be considered the unit bid price for the larger structure. In no case will the owner be
liable for additional payment for structures larger than the size specified.

Encasement structures shall be installed at the grades and alignment shown on the plans.
Deviation shall be permitted only via approval of the Utility.

Where open cut is not practical or permitted, the encasement structure shall be installed
by jacking, boring or tunneling or a combination of these methods unless a particular
method is specified in the plans. Timber or steel guide rails shall be used for any of these
methods. The grade, slope and alignment of the guide rails shall be carefully set in order
to attain the specified grade and alignment.

Pits and trenches shall be sheeted and braced in accordance with OSHA or other
applicable requirements.

Damage to the pipe coating during shipment or handling shall be repaired.

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The excavation and backfill of encasement pipe installed in open cuts shall be in
accordance with the provisions contained elsewhere herein for other pipe.

Smooth wall steel pipe shall be connected by full penetration butt welding.

The construction of encasement structures by tunneling or boring shall be performed to
ensure that settlement of the surface above the structure is minimal. The excavation shall
be performed so that voids around the structures are minimized. Voids around the
periphery of the structures will be filled by pressure grouting if required by Engineer and/or
Utility. The grout shall be 1 part Portland cement and 2 parts sand with water adequate
to permit pumping on encasement structures 24” in diameter and larger. The grout shall
be introduced through suitable fixtures and placed through the structure wall at intervals
adequate to completely fill all voids. The fixtures shall have pressure type caps which will
be closed once the grouting operations have been completed. The grouting pressure shall
be sufficient to completely fill all voids without causing upheaval of overburden above the
encasement structure but shall not exceed 5 psi. If voids exist around structures smaller
than 24” in diameter, Contractor shall introduce grout to completely fill the voids through
suitable borings made from the surface.

19. Concrete Thrust Block & Anchor Collars.

All plugs, caps, tees, reducers, and bends, unless otherwise specified, shall be provided
with thrust blocks and/or suitably restrained joints.

Concrete thrust blocks and anchors shall be provided along the pipe line in accordance
with the construction details, plan sheets or as directed by the Engineer. The concrete
mix shall be Class "A" for anchor collars and Class "B" for thrust blocks.

Concrete for thrust blocks shall be placed against undisturbed soil. The excavation shall
be hand shaped and free of loose material. Forms shall be used to confine the concrete
in areas other than that part that is in contact with undisturbed soil in the direction of the
thrust.

No concrete shall be placed around any part of a joint or placed so that it interferes with
the removal of any joint accessories such as bolts, followers, threads, collars, couplings,
etc. Fire hydrant drains shall not be restricted.

The top of the concrete thrust block or anchor collar shall be struck off with a wood straight
edge or float.

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Concrete shall not be placed when the temperature is below 40o F and dropping or below
35o F if the temperature is rising, unless approved by the Engineer. Placement shall be

in accordance with ACI or PCA recommendations.

Admixtures are not to be used without the approval of the Engineer and/or Utility.

All placement of concrete must be in the presence of the Engineer or his representative.
The Contractor is cautioned that they may be required to remove, without compensation,
any concrete placed in the absence of the Engineer or his representative.

Backfill over concrete thrust blocks or anchor collars shall not be placed before the
concrete has attained initial set. No thrust blocks shall be less than 6" thick between the
pipe line or appurtenances and undisturbed soil in the direction of thrust.

The excavation shall be free of water before concrete is placed. Steel reinforcement, as
specified on the Plans, shall be placed in accordance with ACI, PCA or CRSI
recommendations. The pipe or appurtenances shall be wrapped in plastic before placing
concrete in order to prevent the concrete from making direct contact with the pipe or
appurtenances.

All fittings and valves will utilize Mega Lugs for sizes 4” thru 36”, in addition, these items
will be wrapped in poly wrap prior to placement of concrete.

The area of contact for the thrust blocks and anchor collars shall be sufficient to resist the
thrust. This area will vary depending on the safe bearing value of the soil. Suggested
safe soil bearing values are as follows:

SUGGESTED SAFE BEARING VALUES

Type of Soil (Tons/sq.ft.)

Solid Rock 25

Hard Slate 6

Medium Shale 4

Soft Shale 2

Dry Clay Gravel 4

Soft Clay 1.5

Dry Sand or Loam 2.5

Wet Clay 0.75

The above values are approximate and will vary considerably; they are intended to be
used only as a guide. The Contractor is responsible for determining the soil bearing value
or for taking other action(s) to ensure the bearing area is adequate to restrain the pipe or
appurtenances.

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Where the soil is unstable or in the case of recent fill areas, the following procedures shall
apply either singly or in combination:

(a) Thrust blocks shall be of adequate size to restrain pipe or appurtenances by
mass alone depending on horizontal bearing of the soil.

(b) The excavation shall extend deep enough to contact firm soil and the block
brought up to the pipe or appurtenances and constructed so that the block acts as a beam
and will provide required restraint. Such blocks shall be reinforced with steel reinforcing
bars.

(c) Anchor blocks shall be constructed in a firm soil and tie rods extended to the
pipe or appurtenances.

Thrust blocks for vertical bends shall be adequate to resist the thrust by mass alone when
the thrust is upward.

Thrust blocks and anchor collars shall be adequate to restrain the pipeline and
appurtenances at the specified test pressure. The following table lists the resultant thrust
at certain fittings at a pressure of 100 psi in order to determine the thrust at the test
pressure these values are to be multiplied by a factor equal to the test pressure divided
by 100.

Thrust Per 100 psi Pressure
Thrust (tons)

Fitting 6” 8” 12” 16” 20” 24” 30” 36” 42” 48”

11 ¼o Bend 0.3 0.5 1.1 2.0 3.1 4.4 6.9 10.0 13.6 17.7

15o 0.4 0.7 1.5 2.6 4.1 5.9 9.2 13.3 18.1 23.6

22 ½o 0.6 1.0 2.2 3.9 6.1 8.8 13.8 19.9 27.0 35.3

30o 0.7 1.3 2.9 5.2 8.1 11.7 18. 26.3 35.9 46.8

45o 1.1 1.9 4.3 7.7 12.0 17.3 27.1 39.0 53.0 69.2

90o 2.0 3.6 8.0 14.2 22.2 32.0 50.0 72.0 98.0 128.0

Plug
(Dead End) 1.4 2.5 5.7 10.1 15.7 22.6 35.3 50.3 69.3 90.5

Concrete thrust blocks or anchor collars that fail to restrain the pipe or appurtenances
shall be replaced by the CONTRACTOR at their expense.

Restraining mechanisms for push-on or mechanical joints may be used instead of
concrete backing as approved by Engineer. Tie rods, clamps, or other components of
dissimilar metal shall be protected against corrosion by hand application of a suitable
coating or by encasement of the entire assembly with 8-mil loose polyethylene film in
accordance with AWWA C105.

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20. Concrete Mix.

Class "A" concrete shall have a 28-day compressive strength of at least 3,500 psi and
shall contain not more than 6 gallons of water per sack of cement, including the water in
the aggregates, and not less than 6 sacks of cement per cubic yard of concrete.

Class "B" concrete shall have a 28-day compressive strength of at least 3,000 psi and
shall contain no more than 7 gallons of water per sack of cement, including the water in
the aggregates, and no less than 5 sacks of cement per cubic yard of concrete.

Uses of Concrete by Classification:

Class "A" Concrete shall be used for the following:

(a) Sidewalks, street surfaces, curbing, gutters, ditch paving and driveways.

(b) Structures such as vaults, buildings, retaining walls, protective slabs over
pipelines and other facilities, footings, pipe supports and anchor collars.

Class "B" Concrete shall be used for thrust blocking.

Ready-mix concrete shall be used unless an alternate source of concrete has been
previously approved by the Engineer. Ready-mix concrete shall conform to ASTM
Standard C94 and to applicable portions of these specification(s) for on-site mixing. The
concrete shall be delivered and placed within 45 minutes after all materials, including
mixing water, shall have been placed in the mixing drum. The Contractor shall obtain from
the supplier of the ready-mixed concrete, the supplier's agreement to inspection by the
Engineer, to the full extent deemed necessary by the Engineer.

As the placement of concrete progresses, the Engineer may take samples of the concrete
for testing. The Contractor shall provide whatever assistance required by the Engineer in
collecting and preparing samples for testing. Sampling shall be in accordance with ASTM
Standard C172.

Slump tests shall be made in accordance with ASTM Standard C143.

Compression test specimen(s) shall be prepared and cured in accordance with ASTM
Standard C31. Specimens shall be tested in accordance with ASTM Standard C39.
All reinforcing bars shall be "Billet-Steel Concrete Reinforcement Bars" conforming to
ASTM Designation A15 or "Rail-Steel Concrete Reinforcement Bars" conforming to
ASTM Designation A16. Billet-Steel bars shall be intermediate grade with a minimum
yield point of 40,000 psi.

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All reinforcing bars shall be deformed bars. Deformation shall comply with the "Minimum
Requirements for the Deformation of Deformed Steel Bars for Concrete Reinforcement -
ASTM Designation A305".

When the volume of Class B concrete required at the work site is less than 1/3 cubic yard,
mixing may be accomplished by hand tool methods. The concrete shall be mixed in a
clean, water-tight vessel to the extent necessary to ensure that the cement, aggregate
and water are thoroughly integrated. The mix shall be at least 1 part Portland cement to
2 parts coarse aggregate and 2 parts sand. Only that amount of water required to provide
a stiff, workable mix shall be used.

Hand mixing of Class A concrete is not allowed.

21. Placement & Finishing Class "A" Concrete.

General. Forms shall be constructed before placement of any concrete unless otherwise
authorized by the Engineer.

Forms shall conform to shapes, lines and dimensions of the members as specified on the
plans, or as required to conform to the original shape and dimensions in the case of
replacement structures and shall be sufficiently tight to prevent leakage of mortar. They
shall be properly braced or tied together to maintain position and shape. They may be
constructed of any material with sufficient strength, which will provide the finished work a
satisfactory surface; however, metal forms will not be permitted for concrete, which will
be exposed on any of the completed work, unless approved by the Engineer.

In those cases in which paved surfaces are being replaced such as sidewalks, driveways,
curb, gutter, etc., the edge of adjacent existing surfaces must be cut straight and smooth
using a concrete saw or other suitable tool. The forms shall be constructed in such a
manner that a smooth concrete surface is produced which matches the existing surfaces
on each side.

Forms shall be removed in such a manner to ensure the complete safety of the structure.
When the structure is supported on shores, the removable floor forms, beams, and girder
sides, and column and similar vertical forms may be removed after 96 hours, providing
the concrete will not be damaged. In no case shall supporting forms or shoring be
removed until members have acquired sufficient strength to safely support their weight
and imposed loads.
Forms shall be coated with oil prior to placement of reinforcing steel or concrete.
Excessive coating material shall not be allowed to form or stand in puddles in the forms,
neither is it allowed to come in contact with concrete against which fresh concrete will be
placed.

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Placement of Reinforcement. At the time concrete is placed, metal reinforcement shall
be free from rust scale or other coatings that will destroy or reduce the bond. All bars
shall be shop bent, unless otherwise permitted by the Engineer. No bars partially
embedded in concrete shall be field bent except as shown on plans or as specifically
permitted by the Engineer. Field bending of rail steel bars will not be permitted.

Metal reinforcement shall be accurately placed according to the plans or as specified
herein, adequately secured in position by concrete, metal or other approved chairs,
spacers or ties.

No splices of reinforcement shall be made except as shown on the plans, as specified, or
as authorized by the Engineer. All welding shall conform to the American Welding
Society's Recommended Practices for Welding Reinforcing Steel, Metal Inserts and
Connections in Reinforced Concrete Construction (AWS D12.1), unless otherwise
authorized by the Engineer. All laps and splices shall be in accordance with AC1 318,
using f1c = 3000 psi and fy = 60,000 psi unless otherwise shown on the plans.

The reinforcement shall be protected by the thickness of concrete indicated in the plans.
Where not otherwise shown, the thickness of concrete over the reinforcement shall be as
follows:

(1) Where concrete is deposited against the ground without the use of forms,
not less than 3” clearance must be maintained, except wire mesh
reinforcement for concrete slabs which may be within 1 ½” of the ground.

(2) Where concrete is to be exposed to the weather or to the ground but placed
in forms, no less than 2” clearance for bars larger than No. 5 and 1 ½”
clearance for No. 5 bars or smaller.

(3) In slabs and walls not exposed to the ground or to the weather, no less than
3/4 inches clearance.

(4) In all cases, at least equal to the diameter of the bars.

Reinforcement for sidewalk, ditch paving, slope protection and driveway surfaces shall
consist of 6” x 6” mesh, #6 for driveways and #9 for ditch paving, slope protection and
sidewalks.

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Joints and Joint Filler. Water stops shall be installed for construction joints in walls and
slabs below finished ground elevation and in all water bearing structures. Where a joint is
to be made, the surface of the concrete shall be thoroughly cleaned and all laitance
removed. In addition, vertical joints shall be thoroughly wetted and slushed with a coat
of neat cement grout immediately prior to placement of new concrete.

Expansion and contraction joints shall be provided as shown on the plans, or if not shown
on the Plans shall be provided as follows:

For replacement sidewalk, driveway, curb and gutter sections; transverse joints shall be
spaced in accordance with the spacing of the adjacent surfaces. Longitudinal expansion
joints shall be provided where the section being replaced abuts another structure.
Contraction joints in sidewalks shall be shaped similar to existing adjacent joints.

The spacing of joints for other structures such as ditch paving, protective slabs, etc. shall
be as directed by the Engineer.

Joint Filler. Pre-molded joint filler shall be the non-extruding type, ¾” to 1” thick,
conforming to ASTM Designation M33 and shall be of sufficient dimension to extend
through the full depth of the paved surface.

Poured joint filler shall be bituminous material conforming to ASTM Designation M18 or
rubber-base compound conforming to Federal Specification(s) SS-F-336.

Embedded items, wall fittings and anchor bolts shall be installed as shown on the Plans.
Embedded items shall be worked-out in advance of the concrete pour, allowing the
Engineer ample time for inspection of all items to be embedded.

Placing Concrete. All placement of concrete must be in the presence of the Engineer or
his representative. The Contractor is cautioned that they may be required to remove,
without compensation, any concrete placed in the absence of the Engineer or his
representative.

Equipment for chuting, pumping and pneumatically conveying concrete shall be of such
size and design as to ensure a practically continuous flow of concrete at the delivery end
without separation of materials. All concrete in walls and columns shall be poured through
“tremies” unless otherwise permitted by the Engineer. The free fall of concrete shall be
held to a minimum.

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Concrete shall be deposited as nearly as practicable in its final position to avoid
segregation due to re-handling or flowing. The placing of concrete shall be performed at
a rate that ensures the concrete is at all times “plastic” and flows readily into the spaces
between the bars. No concrete that has been contaminated by foreign material shall be
used, neither re-tempered concrete.

Once placement has begun, it shall be carried on as a continuous operation until
placement of the panel or section is complete. When construction joints are necessary,
they shall be made as described herein.

In placing concrete, care shall be taken that the freshly placed mass is so placed and
vibrated that there is no tendency for the coarse aggregate to segregate from the mortar,
no rock pockets are left, the concrete flows readily around the steel and into the
extremities of the forms and the whole freshly-placed mass becomes a plastic jelly-like
mass but without free water in appreciable quantity on its surface. No Class "A" concrete
shall be poured without the use of mechanical or magnetic internal vibrators.

Water shall be removed from place of deposit prior to placement of concrete unless
otherwise permitted by the Engineer. Prior to depositing concrete on or against concrete
which has taken its initial set, the surface of the hardened concrete shall be broken off
down to coarse aggregate and wire brushed to remove foreign matter and laitance. A
layer of grout of the same cement-sand ratio as the concrete without coarse aggregate
shall be placed to a thickness of 1” to 2” on the brushed surface after which the new
concrete shall be placed immediately.

Concrete placed directly on the ground shall be placed in the forms on a compacted
wetted subgrade and shall be tamped and spaded until mortar covers the entire surface.
Tamping and spading shall be given special attention in order to prevent voids in the
concrete.

The cross section of the curb and gutter shall conform to that of adjacent sections or as
directed by the Engineer. The surface shall be struck off smooth between templates,
shaped to the required cross section and it shall be finished with a wooden float and steel
trowel, then broomed to produce a uniform finish to match that of adjacent sections. The
curb and gutter shall be grooved with an approved grooving tool at intervals equal to those
of adjacent sections where applicable.

Flat Surfaces. After concrete has been deposited, it shall be approximately leveled and
struck off to such depth below the finish grade as required to place reinforcing mats or
wire mesh, it shall be properly consolidated prior to placing the reinforcing mats or mesh,
when applicable. Additional concrete shall be deposited and struck off to a depth above
the finish grade that when properly consolidated, the surface shall conform to the line and
grade required to match adjacent surfaces. The strike-off board shall be straight, free

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from warp, and shod on the striking surface with a steel strip. The strike-off board shall
be moved forward with a combined longitudinal and transverse motion and without raising
either end above the side forms during the strike-off process. A slight excess of material
must be kept in front of the cutting edge at all times.

Immediately following screening and compaction operations, the slab surface shall be
tested for trueness with a straight-edge. Any depressions found shall be filled with freshly
mixed concrete, struck off, consolidated, and refinished. Longitudinal floating shall be
done in conjunction with checking with the straight edge. The float shall not be less than
12”in length, from 8” to 10” in width and shall be properly stiffened to prevent flexibility
and warping. The straight-edge testing and floating operation shall continue until the
entire surface is found to be free from observable departures from the straight edge, and
until the surface of the slab has the required grade and contour.

Concrete Finishing. The concrete shall be worked with suitable tools until a finish which
matches that of adjacent surfaces is achieved.

Exposed aggregated finish. Scrubbed finish shall be produced on green concrete. The
surface shall be thoroughly wetted and scrubbed with stiff fiber or wire brushed, using
water freely, until the surface film of mortar is removed and the aggregate is uniformly
exposed. The surface shall then be rinsed with clean water. If portions of the surface
have become too hard to scrub in equal relief, dilute hydrochloric acid (commercial
Muriatic Acid diluted with 4 to 10 parts water) shall be used after the concrete is a least 2
weeks old to facilitate the scrubbing. The acid shall be removed within 15 minutes from
the finished surface with clean water. This operation may be facilitated by casting the
concrete against form faces which have been coated with a chemical retardant to keep
the mortar adjacent to the form from setting. Every effort must be exerted to ensure the
new surface matches any existing adjacent surfaces.

All exposed inner and outer (above grade) walls of structures shall be finished as follows:
Forms shall be removed from such surface as soon as structurally possible and when
approved by the Engineer. All imperfections and depressions shall then be immediately
filled with mortar. The concrete surfaces shall then be machine or hand rubbed until the
entire surface has a smooth, homogeneous, pleasant-appearing finish of uniform texture
and color. Any delay in patching or rubbing such surfaces shall be cause for rejection of
the entire structure. No mortar or wet cement shall be used in finishing except the mortar
necessary to fill imperfections. Edging tools shall be used on all exposed joints and edges.
All exposed corners shall be chamfered as shown on the plans.

Forms shall be removed from wall surfaces. All imperfections and depressions shall then
be immediately filled with mortar and rubbed with a wooden float or steel trowel to give a
uniform appearance. Spurs shall be removed from the concrete surface. No over-all
machine or hand rubbing is required. Floors of structures and ditch pavement shall be

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trowel finished.

After placement and finishing, concrete shall be protected from damage while curing.
Provisions shall be made for maintaining concrete in a moist condition for a period of at
least 10 days after placement.

After removal of forms and finishing, as specified elsewhere herein, backfill shall be
placed around the structure and thoroughly compacted.

Cold Weather Requirements. Concrete shall not be placed when the ambient temperature
is below 40o F, or when the concrete is likely to be subjected to freezing temperatures
before final set has occurred. Concrete footings or slabs shall not be placed over frozen
ground. The temperature of the concrete when placed shall not be less than 45o F.
Heated materials shall be free of ice, snow and frozen lumps before entering the mixer.
Methods and equipment for the heating of material(s) shall be subject to the Engineer’s
approval. Suitable means shall be provided for maintaining the concrete at a temperature
of at least 45o F for not less than 96 hours after placing.

Special methods shall be used to protect concrete floor slabs in cold weather to prevent
frost from entering the concrete (or fill under floor slabs) until the building or structure is
enclosed and heat is provided. Methods shall include covering of slabs with hay or other
insulating material, protection of insulation from wetting with tarpaulins, introduction of
heat, construction of enclosures or other methods. Depending upon the severity of the
weather, the housing, covering or other protection used in connection with curing shall
remain in place and intact at least 24 hours after the artificial heating is discontinued.
Methods to be used shall be proposed in advance of the work and shall be approved by
the Engineer. Salt, calcium, chloride, or other chemicals shall not be mixed with the
concrete to prevent freezing.

Any and all concrete damaged by freezing shall be removed to the satisfaction of the
Engineer, and replaced at the expense of the Contractor.

Hot Weather Requirements. In hot weather, suitable precautions shall be taken to avoid
drying of the concrete prior to finishing operations. Use of windbreaks, sunshades, fog
sprays or other devices shall be provided as directed by the Engineer.

Concrete deposited in hot weather shall not have a placing temperature that will cause
difficulty from loss of slump, flash set, or cold joints. Concrete temperatures shall be less
than 90o F unless permitted by the Engineer.

The use of curing compounds or other additives shall be prohibited unless approved in
advance by the Engineer.

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22. Backfill.

All backfill material(s) shall be free from cinders, ashes, refuse, vegetable or organic
material, boulders, rocks or stones, frozen soil or other material that is unsuitable.

All trenches shall be backfilled as soon as possible after installation of the pipe line and
appurtenances. It may be necessary to backfill only a portion of the trench in order to
accomadate adequate curing of concrete.

Backfilling under the pipe shall be in accordance with these specification(s).

Donafill, wet or frozen material shall not be used for backfilling.

When trenches cross or pass through existing paved roads, streets or alleys, backfill shall
be in accordance with requirements of state, county or local authority having jurisdiction.

The Contractor shall fill trenches with suitable material where settlement has occurred up
to 90 days after completion of the project.

In areas where sod, trees, shrubs, flowers or other vegetation has been removed and is
to be replanted, the top 6” of backfill shall be suitable bottom land top soil.

Concrete pipe closures and other fittings or appurtenances designated by the Engineer
shall not be backfilled until the hydrostatic pressure and leakage tests have been
completed.

23. Bedding.

All plastic pipe shall be installed as follows:

The trench shall be excavated to a depth at least 6” below plan grade. The trench width
shall conform to the requirements these specification(s). Pipe shall be bedded in a
foundation constructed as shown on the plans and standard details. Bedding material
shall be gravel, crushed stone (maximum diameter of 1 ¼”) or crushed fines (5/8” minus).
Foundation under pipe shall be bedding material 6” in thickness. Bedding Material shall
be used to backfill a height 12” above the top of the pipe. Excavated material shall not be
used for bedding or pipe foundations.

Trenches under pavement require ARDOT Class 7 Gravel for backfill and compaction to
95% Modified Proctor.

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Ductile iron pipe cannot be laid on exposed rock, it shall be backfilled with select backfill
(no rocks larger than 2.5”). If suitable backfill is not available, crushed rock or City Pit
may be used as bedding material up to 4” below and above the pipe.

24. Replacement of Special Surfaces.

The Contractor shall repair or replace all special surfaces removed or disturbed during
the progress of the work.

All replacement or repairs of special surfaces within the right-of-way of public streets or
roads must conform to the requirements of and be approved by the State, County or local
authority having jurisdiction. Concrete surfaces, except street pavement, shall be
constructed in accordance with requirements of the State, County or local authority having
jurisdiction.

The material(s) used shall be of the same type as that removed or material(s) approved
by the Engineer, State, County or local authority having jurisdiction.

The City Standards for street repairs are contained within the City Code for Pavement
Cuts and Utility Work in the Public Right-of-Way.

25. Temporary Repairs to Special Surfaces.

Unless permanent repairs to paved street surfaces can be started within 2 days after
backfilling the trench, Contractor shall place suitable asphalt material in the trench. The
surface shall match the surfaces on each side of the trench and shall be in accordance
with applicable State, County or city requirements.

The above provisions shall apply to driveways, sidewalks, parking lots or other paved
areas whenever the backfill will not adequately support vehicular traffic, whenever dust
from the trench creates a nuisance, or whenever the trench is a hazard.

Detours shall have a gravel, crushed stone or asphalt surface. Dust shall be controlled
by the application of asphalt or water.

The Contractor shall maintain all temporary surfaces in good condition until permanent
repairs are complete.

26. Connections to Distribution System.

All connections to the existing water distribution system shall be accomplished by Utility
personnel, unless specific authorization is given by the Utility in advance which would
permit the contractor to accomplish the connection.

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When authorized by the Utility to accomplish a connection to the existing water
distribution system, all work must be done at the direction of, and in the presence of Utility
personnel.

27. Filling Pipe Lines.

After the pipe lines and appurtenances have been installed, all concrete thrust blocking
has cured adequately and upon approval of the Engineer, the pipe lines shall be filled
with water.

In order to prevent circulation of water through the new pipe lines back into the distribution
system, only one valve shall be opened to allow water to flow into the new pipe lines. This
valve will be tightly closed after the filling operation has been completed. A sufficient
number of hydrants and/or blowoffs shall be opened to allow for proper escape of air
during filling, the same shall be closed as line fills.

The valve operated to fill the pipe lines shall be operated slowly and shall not be fully
opened. The operation of the valve shall be under the direction of the Engineer.

All air shall be expelled from the pipe line by opening fire hydrants and/or other openings
installed at the pipe line crests (high points) by the Contractor. The location and number
of such opening(s) shall be as shown on the plans or as directed by the Utility.

28. Hydrostatic Pressure and Leakage Tests.

Flushing. Foreign material(s) left in the pipeline during installation often result in valve or
hydrant seat leakage during pressure tests. Every effort shall be made to keep lines clean
during installation. Thorough flushing is recommended prior to a pressure test; flushing
should be accomplished by partially opening and closing valves and hydrants several
times under expected line pressure with flow velocities adequate to flush foreign
material(s) out of the valves and hydrants.

Pressurization. After the pipe has been placed, all newly laid pipe or any valved section
thereof shall be subjected to a hydrostatic pressure of at least 1.5 times the working
pressure at the point of testing. Each valved section of pipe shall be slowly filled with
water, pressurized to the specified test pressure, based on the elevation of the lowest
point of the line or section under test and corrected to the elevation of the test gauge, the
pressure shall be applied by means of a pump connected to the pipe in a manner
satisfactory to the Engineer. Valves shall not be operated in either the opening or closing
direction at differential pressures above the rated pressure. It is good practice to allow the
system to stabilize at the test pressure prior to conducting the leakage test. The
Contractor shall furnish the pump and appurtenances necessary for testing. The

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Contractor shall furnish all labor for conducting the tests. The source of water for the pump
suction shall be potable water from the Utility’s distribution system. The vessel used must

be approved by the Engineer.

Air Removal. Before applying the specified test pressure, air shall be expelled completely
from the pipe, valves, and hydrants. If permanent air vents are not located at all high
points, the contractor shall install corporation cocks at such points to enable the air to be
expelled as the line is filled with water. Once all the air has been expelled, corporation
cocks shall be closed and the test pressure applied. At the conclusion of the pressure
test, corporation cocks shall be removed and plugged or left in place at the discretion of
the Engineer.

Examination. Any exposed pipe, fittings, valves, hydrants, and joints shall be examined
carefully during the test. Any damaged or defective pipe, fittings, valves, hydrants or joints
that are discovered following the pressure test shall be repaired or replaced with sound
material and the test shall be repeated until it is satisfactory to the Engineer.

Leakage Defined. Leakage shall be defined as the quantity of water that must be supplied
into the newly laid pipe or any valved section thereof to maintain pressure within 5 psi of
the specified test pressure after the pipe has been filled with water and the air has been
expelled. The minimum duration of the hydrostatic leakage test shall be 2 hours or as
specified by the Utility. Leakage shall not be measured by a drop in pressure in a test
section over a period of time.

Allowable Leakage. No pipe installation will be accepted if the leakage is greater than
that determined by the following formula:

Q = L X D (P) 0.5
148,000

Where Q = Allowable Leakage in Gallons per Hour
L = Length of Pipe Line Tested in Feet
D = Nominal Diameter of Pipe in Inches
P = Test Pressure of Pipe (1.5 times working pressure in PSI)

Acceptance of Installation. Acceptance shall be determined on the basis of allowable
leakage. If any test of laid pipe discloses leakage greater than that specified above, the
Contractor shall, at their own expense, locate and make approved repairs as necessary
until the leakage is within the specified allowance.

Once the specified test pressure has been applied, the entire pipe line shall be checked
in the presence of the Engineer and Utility giving particular attention to that part of the
pipe line and those appurtenances that are exposed.

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All visible leaks are to be repaired, regardless of the amount of leakage.
A pressure test report of the main shall be provided to the Utility with the Engineer of
Record’s signature.
29. Test Pump.
The Contractor shall provide a water pump for testing the mains hydrostatically. The pump
shall have the following features:
Designed so that the required test pressures can be attained.
Pump must be equipped with a by-pass pipe between the pump suction and discharge.
By-pass shall be equipped with an in-line valve and a valved exhaust outlet.
The pump discharge shall be equipped with the following, in the order listed from the
pump outward:

(a) Pump by-pass outlet.
(b) Check valve arranged so as to prevent flow back toward pump.
(c) Adjustable pressure regulating device capable of maintaining discharge

pressure at a constant level.
(d) Valved exhaust outlet.
(e) Section of flexible hose - length sufficient that ends of hose rests on ground.
(f) Straight meter coupling - 1/2" M.I.P. x 5/8" Meter Nut.
(g) 5/8" meter - furnished by Utility.
(h) Straight meter coupling - 1/2" M.I.P. x 5/8" Meter Nut.
(i) Outlet for pressure gauge. Outlet shall be equipped with valve and surge

dampening device. Connection for gauge shall be 1/4" F.I.P. The pressure
gauge will not be furnished by Utility.

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The pump suction shall be equipped with the following from the pump outward (see
Standard Detail Sheet):

(a) Pump by-pass outlet.

(b) Suction pipe.

(c) End screen to prohibit entry of foreign matter if pump suction is connected
to a vessel instead of on a water main.

The Contractor shall provide all other necessary connections for connecting pump from
the suction source and to the main being tested.

30. Disinfecting Pipe Lines & Appurtenances.

General. All new water mains shall be disinfected in accordance with AWWA C651 prior
to being placed in service. The record of compliance shall be the bacteriological test
results certifying the water sampled from the water main to be free of coliform bacteria
contamination. Utility will obtain required samples and perform required testing to confirm
acceptability of main(s).

Preventive and Corrective Measures During Construction. Precautions shall be taken to
protect the interiors of pipes, fittings and valves against contamination. Pipe delivered for
construction shall be strung to minimize entrance of foreign material. All openings in the
pipeline shall be closed with watertight plugs when pipe laying is stopped at the close of
the day's work.

If dirt enters the pipe, and in the opinion of the Engineer the dirt will not be removed by
the flushing operation, the interior of the pipe shall be cleaned by mechanical means and
then disinfected. Cleaning with the use of a pig, swab, or "go-devil" should be undertaken
only when the Engineer has determined that such operation will not force mud or debris
into pipe-joint spaces.

Methods of Disinfection. There are three acceptable methods of disinfecting: continuous
feed method using liquid chlorine or calcium hypochlorite, the slug method using liquid
chlorine or calcium hypochlorite and the tablet method using calcium hypochlorite. The
slug method applies to large mains and shall be used only upon the approval of the
Engineer. Liquid chlorine shall be used only when the Contractor has suitable equipment
available and employees who are familiar with the physiological, chemical and physical
properties and who are properly trained and equipped to handle any emergency that may
arise. If, in the opinion of the Engineer, the equipment is inadequate or the personnel are
not qualified, this method shall not be used.

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When the continuous feed or slug method is to be used, the pipe lines and appurtenances
shall be thoroughly flushed prior to disinfecting. The flushing plan shall be approved by
the Engineer. The Engineer may halt or reduce flushing if the distribution system
pressures are reduced by the flushing operations.

The Contractor is reminded that chlorine is a powerful oxidant and reacts readily with
foreign substances. All chlorine compounds shall be handled and stored in accordance
with manufacturer(s) recommendations. Breathing of chlorine gas can be fatal.
Hypochlorite solutions should not come into contact with the skin or clothing. Containers
used for mixing hypochlorite solution shall be clean and dry.

When the continuous flow or tablet method is used, final concentration of chlorine inside
the main shall be 50 ppm (parts per million). The concentration of chlorine entering the
pipe line when the slug method is used shall be at least 300 to 400 ppm (parts per million).

Calcium hypochlorite shall contain 60% available chlorine by weight either in tablet or
granular form.

When the continuous feed or slug method is used and the source of chlorine is calcium
hypochlorite, a solution of hypochlorite and water shall be prepared by mixing thoroughly
in a suitable container. The mix shall contain 1 pound of calcium hypochlorite per gallon
of water. A suitable pump shall be provided for pumping this solution into the pipe lines
to be disinfected. This pump shall be equipped with a flow measuring device.

When liquid chlorine is used, the equipment for injection shall consist of a solution feed
chlorinator in combination with a booster pump for injecting the chlorine-gas water
solution into the pipe line. Introduction of chlorine-gas directly from the supply cylinder
shall not be permitted. The pump shall be equipped with a flow measuring device.

During application of any chlorine solution, care shall be taken to ensure the solution does
not flow back into the distribution system.

The procedures for disinfecting by the continuous flow method shall be as follows:

The flow through the pipeline and the solution flow shall be regulated to attain the required
concentration of chlorine. The flow through the main shall be measured by using a pitot
gauge or meter.

The introduction of the solution shall be continuous until the desired concentration is
attained throughout the pipeline system. The concentration shall be checked by the Drop
Dilution Method.

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After the required concentration has been attained all internal valves shall be operated in
order to ensure the solution comes in contact with all appurtenances.

The solution shall remain in the pipe line system for 24 hours after which the pipe lines
shall be thoroughly flushed. The chlorine concentration shall be checked before flushing.
If the concentration is less than 25 ppm (parts per million) the disinfecting procedure shall
be repeated if directed by the Engineer.

The procedure for disinfecting by the slug method shall be the same as the continuous
flow method except that the flow rates shall be regulated so that the specified
concentration of chlorine shall be in contact with all parts of pipeline for at least 1 hour.

Final Flushing. After the applicable retention period, heavily chlorinated water should not
remain in prolonged contact with pipe. In order to prevent damage to the pipe lining or
corrosion damage to the pipe itself, the heavily chlorinated water shall be flushed from
the main until chlorine measurements show that the concentration in the water leaving
the main is no higher than that generally prevailing in the system or is acceptable for
domestic use.

Bacteriological Tests. After final flushing and prior to the water main being placed in
service, two samples taken 24 hours apart shall be collected from the end of the line at
sample points provided by Contractor, samples shall be tested for bacteriological quality
in accordance with Standard Methods for the Examination of Water and Wastewater and
shall show the absence of coliform organisms.

Samples for bacteriological analysis shall be collected in sterile bottles treated with
sodium thiosulfate in accordance with Standard Methods for the Examination of Water
and Wastewater. No hose or fire hydrant shall be used in the collection of samples. A
corporation cock may be installed in the main with a copper-tube gooseneck assembly
for sample collection.

The bacteriological samples shall be submitted to the Arkansas Department of Health
Laboratories for analysis or to a laboratory certified by the Department of Health for
performing such tests.

If the initial disinfection fails to produce satisfactory bacteriological samples, the main
shall be flushed again and shall be re-sampled. If repeat samples show the presence of
coliform organisms, the main shall be re-chlorinated utilizing the continuous-feed or slug
method of chlorination until satisfactory results are obtained.

31. Work Performed by Utility.

The intent of these specification(s) are for the Contractor to do all the work, including connections
and repair of damage to the Distribution System.

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In emergencies, to restore service, the Utility, with its labor forces will assist the Contractor when
necessary at the discretion of the Utility.
If the Utility assists the Contractor for any reason, the Contractor shall reimburse the Utility for the
cost of this assistance, based on the cost of labor, equipment, materials and overhead.
32. Damage to Distribution System.
During the course of construction under this contract, whether by accident or carelessness, if the
distribution system is damaged, the Contractor shall be held responsible for this damage and
shall make immediate repairs at his expense. In the event service has been disrupted, immediate
repair operations shall be continuous and around the clock, if necessary.
33. Clean-Up of Job Site.
The Contractor shall remove all material(s), equipment, tools, temporary structure(s), barricades,
trees and other vegetation that have been cut or may have died as a result of the project. This
includes both public and private property along the project route. There shall be no burning along
the project route unless approved in advance by the Engineer and other agencies involved.

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SECTION THREE
SPECIFICATIONS AND DETAILS FOR WASTEWATER CONSTRUCTION

TABLE OF CONTENTS

ARTICLE I. WASTEWATER SYSTEM MATERIALS 80
80
1. General 81
2. Sanitary Wastewater Pipe 82
3. Pipe Fittings 82
4. Plug Valves 84
5. Manholes 86
6. Epoxy Coated Manholes 87
7. Pipe Bedding Material 90
8. Low Pressure Wastewater System 91
9. Simplex Grinder Pump System 94
10. Duplex Grinder Pump System
11. Air and Vacuum Release Valves

ARTICLE II. WASTEWATER SYSTEM CONSTRUCTION METHODS 96
96
1. General 101
2. Excavation, Bedding, and Backfilling 101
3. Dewatering of Trenches 102
4. Sheeting and Shoring 104
5. Pipe Laying 106
6. Pipe Joints 106
7. Pipe Fittings 108
8. Manholes 108
9. Concrete and Reinforcing Steel 109
10. Pavement Repairs 109
11. Backfill Density Tests 109
12. Methods of Testing
13. Wastewater Line Testing

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ARTICLE III. GREASE TRAPS, INTERCEPTORS, SEPARATORS AND GREASE
RECOVERY DEVICES

1. General 115

2. Grease Traps, Interceptors, Separators and Grease Recovery Devices 115

3. General Specifications 115

4. Grease Trap, Separator, Interceptor and Grease Recovery Devices 116

5. Interceptor and Separator Specifications for Wash Bays 117

6. Operation and Maintenance 118

7. Grease Trap, Separator, Interceptor or Grease Recovery Device Treatment 119

8. Inspection and Cleaning Schedules 119

9. Plan Approval 120

10. Certificate of Occupancy 120

11. Variances 120

12. Best Available Technology 120

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ARTICLE I. WASTEWATER SYSTEM MATERIALS

1. General.

This section of the specification(s) shall govern all materials used in the construction of sanitary
wastewater facilities under the jurisdiction of the City of Hot Springs Utility Department. Projects
that would involve materials other than those included in this specification(s) shall be approved
by the City of Hot Springs on a case by case basis. All request(s) for consideration of alternate
material use shall be submitted on the request form as presented in the specification(s).

The top of all Manholes, Grinder Stations and Pump Stations will maintain a minimum
elevation 6” below finished slab of lowest building. In the event this is impractical, use of
a back flow preventer is required.

2. Sanitary Wastewater Pipe.

All sanitary wastewater pipes shall be Polyvinyl Chloride (PVC) or High Density
Polyethylene (HDPE).

Polyvinyl Chloride (PVC) Wastewater Pipe. PVC pipe for sanitary wastewater gravity mains
up to 21” in diameter shall conform to the current ASTM designation D-3034, for 4”-15”, F- 679
for 18”-21” PVC and shall be not assembled with glued joints. They shall be PVC gravity
wastewater pipe SDR-26 or SDR-35 unless specified otherwise. Any proposed gravity
wastewater main with a diameter larger than 21” shall be reviewed by the Utility on a case by
case basis with regards to pipe material.

PVC Pipe for wastewater force mains up to 12" diameter shall conform to the current
ASTM designation D-2241, PR 250 (SDR-17). Any proposed force main with a diameter
larger than 15” shall be reviewed by the Utility on a case by case basis with regard to pipe material.

Provisions must be made for contraction and expansion at each joint with an elastomeric
gasket. The bell shall consist of an integral wall section with a solid cross section elastomeric
gasket factory assembled, securely locked in place to prevent displacement. Standard lengths
shall be 20’ and 12.5’ + 1”. All fittings and accessories shall be as manufactured and furnished
by the pipe supplier or approved equal and have bell and/or spigot configurations identical to that
of the pipe. Elastomeric gasket shall conform to ASTM Specification D1869. Minimum "pipe
stiffness" at 5% deflection shall conform to ASTM D3034 and D3033 for all sizes when tested
in accordance with ASTM Designation D2412 (External Loading Properties of Plastic Pipe by
Parallel-Plate Loading). Pipe and fittings shall be tested in accordance with ASTM
Designations D2412, D2152, and D2444.

Encasement Pipe. Steel encasement pipe shall be smooth wall, welded steel pipe of the size
and wall thickness and shall be approved by the Utility. Steel pipe shall conform to the
requirements of AASHTO Designation M-190 for Type C Coating.

Wall thickness or gauge shall be shown on the drawings and approved by the Utility.

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The annular space between the inside of the encasement pipe and the wastewater pipe
shall be as shown on the plans. Casing spacers (Stainless or Plastic as applicable) shall
be used. State highway crossing(s) shall conform to requirements of current ARDOT
specification(s).

Pipe Joints. Joints shall be the rubber gasket push-on type, conforming to the requirements
of ASTM Designation D3139. All joints shall meet the requirements as required by current
manufacturers recommendations and shall be approved by the Utility.

All joints for smooth wall steel encasement pipe shall be welded joints unless otherwise
approved.

Service Lines. All service lines shall meet with the requirements of the Arkansas State
Plumbing Code and applicable City Plumbing Codes. Service lines under paved areas shall
be bedded, as required for mains, from the main to the limits of the pavement.

Minimum size for any service line or building wastewater shall be 4” normal diameter.
Size of service line for multi-family or non-residential applications shall be as required in
accordance with Arkansas State Plumbing Code, latest revision.

Service lines larger than 4" shall be constructed of material approved for main extensions
by the Utility.

A clean out is required on wastewater connections at nearest point to the backside of curb
at the city, county or state maintained street or the property line. Cleanout shall include a
cast iron valve box top and sewer lid.

3. Pipe Fittings.

Gravity Wastewater. For gravity wastewater, all bends, tees, plugs, adaptors, wyes, or
other fittings shall meet the requirements of the type and kind of pipe used. All joints shall
meet the requirements for the joints listed above.

Force Main Wastewater. For Force Mains, all bends, tees, plugs, adaptors, reducers, wyes and
other fittings shall be ductile iron mechanical joint conforming to ANSI/AWWA Standard
C100/A21.10 and C111/A21.11. (For pipe sizes 4” and larger)Special Fittings. All special
fittings shall be in accordance with the pipe manufacturer’s recommendations and as
approved by the Utility Connections between different kinds of pipe and future
connections shall be detailed on the plans. Connections shall be such as to provide
watertight joints and shall be approved by the Utility.

Couplings. Connection between plain ends shall be Max Adaptor Couplings or equal approved
by the Utility.

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4. Plug Valves

All plug valves 4” and greater in size shall be Eccentric Plug Valves suitable for
wastewater service with pressures up to 175 psig. Plug Valves shall be quarter-turn,
100% port eccentric, with a resilient encapsulated plug. Eccentric plug valves shall be
designed, manufactured and tested in accordance with American Water Works
Association Standard ANSI/AWWA C517. All Plug Valves shall be certified Lead-Free in
accordance with NSF/ANSI 372.

Flanged valves shall have flanges with drilling to ANSIB16.1, Class 125. Mechanical Joint
valves shall fully comply with ANSI/AWWA C111/A21.11.

Valve bodies and covers shall be constructed of ASTM A126 Class B for working
pressures up to 175 psig. The words, “SEAT END” shall be cast on the exterior of the body
seat end. 4”and larger pugs shall be of one- piece construction and made of ASTM A536 Grade
65-45-12 ductile iron and fully encapsulated with resilient facing per ASTM D20000-BG and
ANSI/AWWA C517 requirements. Plug valves shall have radial shaft bearings constructed to self-
lubricating Type 316 stainless steel. The thrust bearings shall be PTFE. Cover bolts shall be
corrosion resistant with zinc plating.

Valves 4” to 8” shall be equipped with a 2 inch square nut for direct quarter turn operation
with a hand lever. The packing gland shall include a friction collar and an open position
memory stop. The friction collar shall include a nylon sleeve to provide friction without
exerting pressure on the valve packing. When specified, valves 4” and larger shall include a
totally enclosed and sealed worm gear actuator with position indicator (above ground service
only) and externally adjustable open and closed stops. The worm segment gear shall be ASTM
A536 Grade 65-45-12 ductile iron with a precision bore and keyway for connection to the
valve shaft. Bronze radial bearings shall be provided for the hardened worm. All gear
actuators shall be designed to withstand, without damage, a rim, pull of 200lb. on the
hand wheel and an input torque or 300ft-lbs. for nuts. Buried service actuators shall be
packed with grease and sealed for temporary submergence to 20 feet of water. Exposed
worm gear shafts shall be stainless steel.

The exterior of the valve for above ground service shall be coated with a universal alkyd
primer. Valve exterior for buried service shall be coated with an epoxy coating. Each valve
shall be marked with a Serial Number, Manufacturer, Size, Cold Working Pressure (CWP)
and the Direct and Reverse Actuator Pressure Ratings on a corrosion resistant
nameplate. Plug Valves shall be as manufactured by Val-Matic, DeZurik, or equal as
approved by the Utility.

5. Manholes.

General. Work to be performed under this item shall include all work necessary to ensure
an acceptable manhole installation. Manholes may be constructed of precast concrete or
concrete poured in place as detailed on the plans.

Concrete. Concrete used in construction of this item shall be proportioned to produce a 28 day

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compressive strength of 4000 psi minimum and contain 6 bags of cement per cubic yard.

(1) Cement shall be an approved brand and type of Portland Cement conforming to
ASTM Standard Specification C150 and may be either Type 1 or Type 3.

(2) Sand for concrete shall be sharp, clean and uniformly graded silica sand
conforming to ASTM Standard Specification C33 and shall all pass a ¼”
screen.

(3) Gravel for concrete shall conform to ASTM Standard Specification C33 and shall
grade uniformly from 1 ½" to No. 4 size unless the conditions of placement require
the use of small size coarse aggregate.

(4) Water used in making mortar or concrete shall be clean and free from oil,
acid, alkali, sugar or other deleterious substances.

Mortar. Mortar shall be composed of one part Portland cement to three parts fine
aggregate by volume to which shall be added seven pounds of hydrated lime with each
sack of cement. Masonry cement shall be strictly prohibited for use in any part of manhole
construction.

Brick or Block Manholes. Brick or block manholes are not acceptable.

Precast Manholes. Precast concrete manholes are allowed.

Poured In Place Manholes. Poured in place manholes are allowed.
Drop Manholes. Materials used in the construction of drop manholes shall conform to the
requirements of the above paragraphs and other applicable parts of this specification(s). The
fittings and pipe sections of the drop shall be as approved by Utility. All drops shall be
constructed as inside drops.

Manhole Rings and Covers. Metal used in manufacturing of municipal castings shall
conform to ASTM A-48, Class 35B Gray Iron. Castings shall meet requirements of
AASHTO M-306.

Castings shall be manufactured true to pattern; component parts shall fit together in a
satisfactory manner. They shall be of uniform quality, free from sand holes, shrinkage,
cracks or other defects, and be smooth well cleaned by shot-blasting and furnished without
paint for verification.

All circular manhole frames and covers shall be furnished with mechanical horizontal
bearing surfaces unless a non-rocking feature is specified.

Manufacturers shop drawing shall be submitted to the Engineer for approval prior to the
manufacturer or shipment of castings to the job site. The Engineer shall retain the right to
reject castings not conforming to these specification(s).

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Combined weights of manhole ring and cover shall not weigh less than 247 pounds. The
size of opening shall be 24". The words “SANITARY SEWER” shall be cast into the lid.
Manhole lids cast with the City of Hot Springs logo are required by Utility.

Acceptable foundries: Deeter and East Jordan Iron Works or approved equal.

Manhole Steps. Manhole steps shall not be installed in new manholes unless otherwise
specified by Utility.

Hydraulic Plug. Fast setting cementitious water stop may be used to plug hydrostatic leaks
in the structure. Plugging materials shall be special cements and admixtures which are
designed to instantly stop running water or seepage in all types of concrete and masonry
structures. Fast setting water stop: Hydra-plug manufactured by Quadex Corporation,
Strong-Plus manufactured by Strong Seal, or approved equal.

Patching Material. Special rapid setting high strength patching material may be used to repair
the invert and bench areas as well as other sections of the structure that will be under the normal
water line. This rapid setting material must have a curing time of 15 minutes or less, a compressive
strength of 4000 psi or greater within one hour of application. Material must have the ability to be
applied in a thickness up to 8” with no adverse effect on the curing or the structural appearance
(no shrinkage, cracks or voids). This material must cure to a compressive strength of no less
than 1000 psi within 28 days of application. Special rapid setting patching material:+ Hyperform
as manufactured by Quadex Corporation, QSR Patching material as manufactured by Strong
Seal, or approved equal.

Manufacturers Recommendations. Materials, mixture ratios, and procedures utilized for
the coating process shall be in accordance with manufacturer’s recommendations.

6. Epoxy Coated Manholes.
Manhole Lining. The Contractor shall be responsible for the furnishing of all labor,
supervision, materials, equipment, and testing required for the completion of interior
coating of manholes in accordance with the Contract Documents.
Manholes to be coated may be of pre-cast or poured concrete construction. Some may
have a previously applied interior mortar coating.

Minimum Experience Requirements. The Contractor shall demonstrate an experience
requirement of a minimum of 5,000 vertical feet or 900 manholes of interior coating
according to these specifications.

Interior Coating
The coating material should be 100% solids based epoxy binder with fibrous and flake
fillers, as manufactured by Warren Environmental System and designated as S301-14,
or approved equal. Epoxy coated Manholes are required 1000 feet from a pump station
or 1000 feet from the point where a force main enters a gravity main.

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Material Identification
Contractor shall completely identify the types of grout, mortar, sealant, and/or root control
chemicals proposed and provide case histories of successful use or defend the choice of
grouting materials based on chemical and physical properties, ease of application, and
expected performance.

These grouting materials shall be compatible with Warren Environmental System S301-
14 interior coating. The contractor shall be responsible for obtaining compatibility letters
from Warren Environmental system and the grouting material manufacturer prior to the
use of the grouting materials.

Mixing and Handling
Mixing and handling of interior coating shall be in accordance with the recommendations
of the manufacturer and in such a manner as to minimize hazard to personnel. It is the
responsibility of the contractor to provide appropriate protective measures to ensure that
materials are under control at all times and are not available to unauthorized personnel
or animals. All equipment shall be subject to the approval of the Engineer. Only personnel
thoroughly familiar with the handling of the coating material shall perform the coating
operations.

Execution General
Manhole coating shall not be performed until sealing of manhole frame and grade
adjustments, partial manhole replacement; manhole grouting or sewer
replacement/repairs are complete.

Preliminary Repairs
All surfaces to receive the interior coating shall be decontaminated and cleaned using
high pressure water cleaning (minimum 5,000 psi at 5gpm) using a zero degree rotating
nozzle tip, or other suitable method. Cleaning equipment shall have a pressure gauge
that indicates the water pressure being used.

Existing roots and manholes steps shall be removed by cutting them flush with the wall
of the manhole.

All unsealed lifting holes, unsealed step holes, voids larger than approximately one-half
(1/2) inch in thickness shall be filled with patching compound at prior to spray application
of the interior coating.

Temperature.
Normal interior coating operation shall be performed at temperatures of 40 degrees F or
greater.

Interior Manhole Coating
All constructed manholes either pre-cast or cast in place shall be coated. The interior
coating shall be applied to the manhole from the frame to the bench/trough, including the
bench/trough.

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The interior coating shall be applied in accordance with the manufacture’s
recommendations and the following procedures:

1. The surface shall be thoroughly decontaminated and cleaned to provide a
sound surface with adequate profile and porosity for the interior coating to
obtain a good bond to the substrate.

2. Place covers over invert to prevent extraneous material from entering the
sewer.

3. Prior to application the surface may be damp but shall not have noticeable free
water droplets or running water. Materials shall be spray applied by a Certified
Applicator of the interior coating manufacturer utilizing spray equipment
approved by the interior coating manufacturer to an average uniform thickness
of 125 mils for all manholes. After the walls are coated, the bench covers shall
be removed and the bench sprayed to the same average and minimum
thickness as required for the walls.

4. Contractor shall use flow-through plug to bypass flow in the manhole prior to
applying the epoxy coating to the invert. The invert may be damp but shall not
have noticeable running water prior to application. The contractor shall allow a
minimum of four (4) hours cure time before the invert is subjected to active flow.

5. No application shall be made to frozen surfaces or if freezing is expected to
occur inside the manhole within 24 hours after application.

6. Pre-cast and cast-in-place manholes must have a cure time of a minimum of
30 days prior to applying the interior manhole coating.

Testing of Rehabilitated Manholes
After the epoxy liner has set (hard to touch), all visible pinholes shall be repaired. Repairs
shall be made by lightly abrading the surface and brushing the lining materials over the
area. All blisters and evidence of uneven coverage shall be repaired according to the
manufacture’s recommendations. Spot check of coating thickness may be made by
Owner’s Representative (with the Contractor’s assistance), and the Contractor shall
repair these areas as required, at no additional cost to the Owner.

Testing of rehabilitated manholes for water tightness shall be performed by the Contractor
after operations are complete in accordance with the Manhole Testing requirements in
the specification.

7. Pipe Bedding Material.

General. All pipe shall be bedded in a foundation constructed as shown on the plans and
standard details. Bedding material shall be gravel, crushed stone (maximum diameter of
1 ¼”) or crushed fines (5/8” minus). Foundation under pipe shall be bedding material 6” in
thickness. Bedding Material shall be used to backfill a height 12” above the top of the
pipe. Excavated material shall not be used for bedding or pipe foundations.

Where the Contractor exceeds the maximum trench width to the extent that excessive
backfill loads are imposed on the pipe, as determined by the Engineer, the Contractor will

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provide such additional pipe foundation as the Engineer may require without any
additional compensation.

Bedding material shall be Class 1 as defined in ASTM Specification D2321. This Class
includes graded stone, crushed stone and a number of fill materials which are found
locally and have been used successfully for this purpose, if approved by the Utility.

It is a requirement of these specification(s) that the bedding and initial backfill material to
be used be approved by the Engineer prior to construction and that the supplier of such
materials certify to the Engineer that each load supplied conforms to the Class 1
specification(s).

8. Low Pressure Wastewater System.

General. Pressure Wastewater Systems for individual residences are not to be preferred
or used in applications that can be reasonably be served by Gravity Wastewater Systems.
Each Pressure Wastewater System shall be approved by the Utility on a case by case basis.

Pressure Wastewater Systems shall be planned and designed to incorporate an approved limited
area with defined boundaries. The designing Engineer shall specify the limits of ultimate
development with consideration given to the number and types of residential and commercial
units projected for the area.

Use of a Hot Tap process for wastewater line(s) will be approved following review of the
request based on a case by case basis.

System Design. Design shall include a plan and profile drawing to the main line pressure
wastewater system clearly showing the size and elevation of all main line piping. The vicinity of
the proposed pump locations on the lots, tap and stub out locations, valves, point and elevation
of discharge, etc. shall all be clearly indicated on the plans. For ease of identification all pipe
branches shall be separately numbered or otherwise identified.

Clean out and flushing stations shall be incorporated into the pipe layout. Cleanouts shall
be installed at the terminal end of each main, at intervals of 1500’ on straight runs and
whenever two or more mains come together and feed into another main.

Mains shall be designed to achieve a minimum velocity of 2’ per second, based on
manufacturers’ recommendations for general sizing guidelines:

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Design parameters:

Residential

1 Dwelling Unit Simplex 2hp

2-25 Dwelling Units Duplex 2hp

26-100 Dwelling Units Duplex 5hp or 7.5hp

>100 Duplex Non Clog

Commercial
Duplex, 2hp, 5hp or “Non Clog” dependent on flow rate and head conditions

The Low Pressure Wastewater System shall be designed for normal pressures of 40 psi or
less. Mains shall be a minimum of 2” inch in diameter with design velocities between 2’ ft.
per second and 5’ ft. per second. (Note: Individual Grinder pumps typically utilize 1 ¼” service
lines (in the event 3 or fewer Grinder Pumps utilize a single main the requirement to maintain
clean out velocity may impose the need for a 1 ½” main.)

The system should be designed such that the maximum heads at the branch ends
approximate 92’. This will provide optimum scouring velocity, minimum sewage holding
capacity and the most economical pipe installation. (Note: Engineer may submit
appropriate calculations to validate requested deviation from specifications as noted).

Pipe Material. Polyvinyl Chloride (PVC) Wastewater Pipe. PVC pipe for mains and service
lines of the Low Pressure Wastewater System shall conform to current ASTM D-2241 PVC pipe
SDR-17 PR 250, IPS - PVC gasket pipe.
Force Mains shall have a 30” minimum depth of cover over the top of pipe. A continuous
#12 gauge copper coated wire shall be installed with all non-metallic pipe including service lines.
The wire shall run continuously 6 inches above the top of the pipe. The wire shall be looped
around valves, saddles, curb stops and other appurtenances in such a manner that there
is no interference with the operation of the appurtenances. Valve locate boxes shall have signage
provided indicating Utility line(s) in place. In addition locate wire connection(s) shall be affixed to
signage post.

Valve Material. Isolation valves shall be bronze gate valves Class 125 Threaded Non-
rising Stem, Screwed Bonnet, Solid Wedge Disc Crane No. 438 or equivalent.

Check valves shall be bronze swing type Class 125 Threaded, Bronze Disc, "Y" Pattern,
Screwed Cap Crane No. 37 or equivalent.

Preassembled “Lateral Kits” containing both the ball and check valve are also acceptable.

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Construction Methods and Policies. Low Pressure Wastewater System(s) shall be constructed
according to the standard methods as outlined in the general section of the specification(s)
contained herein, except for the following special construction specification(s).

Service lines from individual residence(s) shall be PVC SDR-21 Class 200 pipe. Service
lines shall be 1 ¼” diameter or larger as specified by the Engineer and approved by the Utility.
Service lines shall be buried a minimum of 18” below finish grade. Isolation valves and check

valves shall be installed in a single valve box at the property line at a location approved by the

Utility. The valve box may be plastic and shall be a type and size approved by the Utility.
Ensure “wastewater connection box” is compliant with minimum distance requirements when

placed near Water line(s). The service line as stated above shall be maintained by the

property owner from the connection at the stainless nipple to the check valve at the tap.

Tracer wire for non-metallic pipe: locate wire shall be #12 gauge copper coated wire and
shall run continuously along the “top of the pipe” for all plastic (PVC) pipe(s).

Cost and installation of the grinder pump system shall be provided by the property owner
or improvement district. All material and labor shall be warranted by the installer and/or
supplier for a period of one (1) year after the system is placed in operation. The Utility will provide
maintenance and service as required due to normal wear and tear for the pump and controls,
check valve and isolation valve at the main after the one (1) year warranty period. Actual
cost(s) to repair failures due to abuse by the owner shall be paid by the owner.

The property owner shall be responsible for proper maintenance, upkeep and
replacement of the service line and power supply.

Property owners and developers shall furnish all easements and access required by the

Utility to properly maintain and service the wastewater mains and associated pumping

equipment. Roads utilized to access Utility maintained equipment will be constructed using
“all weather service” material(s) and will require Utility approval.

The property owner shall not bury, build over or in any other way make inaccessible the
lines and pumps for which the Utility is responsible.

When grinder pump systems are included in a wastewater extension, the
developer/owner shall furnish the Utility, without cost, the number of complete
pump/motor assemblies according to the following schedule:

Grinder Pumps Spares Furnished to Utility
1 – 10 1
11 – 20 2

21 or more 10% (Add one for any fraction)

Service Line. The 1 ¼” discharge line and service line shall be installed 24” below the top of the

basin. A section of stainless steel pipe shall be connected to the basin and extend a minimum of
2’ or to a longer length if required to reach the service line trench having an undisturbed trench

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bottom. The service line shall be pressure tested from the basin connection to the force main prior
to final installation of the pump assembly.
The pressure test shall be performed in accordance with the Force Main Leakage Test
procedure as outlined in the general section of the specification(s) contained herein.

9. Simplex Grinder Pump System.

General. Simplex (one pump) grinder pump systems mounted in a fiberglass sewage
collection basin shall be provided for each single family dwelling. A duplex will be
considered as two homes and a simplex grinder station will be required for each unit. If a
single simplex grinder pump station has been previously approved by the Utility to serve
two homes, then both homes shall provide complete electrical circuits to the station
control panel. More than two dwelling units, including three separate houses, a triplex, fourplex,
or apartment complex will require a duplex installation.

Manufacturer/Supplier of the Simplex Grinder Pump System shall furnish the Utility with
a minimum of two operations and maintenance manuals along with the parts lists.

The installation of the pumping unit shall be performed by the Utility. Installation of all other
components including the basin, piping, valves, control panel, etc. shall be performed by a
licensed plumber. The piping inside the lift station wet well shall be stainless steel.

Provide right of entry from the street to the grinder station. No trees or shrubs may be
planted over the sewer lines. Clear access must be maintained for maintenance crews.
Provide a Sensus SCADA grinder monitoring and transmitting alarm system with backup
power. An audio-visual alarm system may be used as a secondary system to the Sensus
alarm.

Pump Design. The pump shall be of a centrifugal design for submersible use and shall have
a 2 HP rating. The 2 HP pump must include internal start and run capacitors. The sewage
cutter/grinder mechanism shall be of hardened and ground stainless steel capable of
macerating solids into fine slurry. The grinder cutting impeller shall extend beyond the
shredding ring to minimize the possibility of large solids clogging the suction inlet. Recessed
grinder cutting impeller designs will not be acceptable. Solid displacement type pumps will not
be accepted, such as Environment One, E1, E1 Extreme or Delta or Omnivore.
Acceptable pumps are Barnes, Hydromatic or Myers.

Fiberglass Basin. The basin shall be fiberglass and be manufactured to be watertight through
a filament wound or hand lay-up system and shall be a type of construction strength and material
approved by the Utility. A resin rich mixture shall be used. Stainless steel fasteners shall
be encapsulated in the top lip to which a cover of fiberglass shall be bolted. Finished
dimensions shall be 30” diameter by 60” or 72” deep as required by elevation of piping. The
circumference of the basin bottom shall be equipped with anti-flotation hold downs which shall
be embedded in concrete. Basin shall be backfilled with select material containing no rocks or
stones larger than 3”. The top of the basin shall be a minimum of 6” below the floor elevation

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of the building it serves and 4” above site finished grade with positive run off grade on all
sides. The basin and pump assembly shall be located a minimum of 10’ from all buildings
and water systems. The location of a grinder shall not be in a depression where storm
water collects or is channeled.

Control Panel. Hercules brass lock shall be furnished with each control enclosure. All locks
furnished for the system shall be keyed alike such that only one key will be required to
open all panels. Keys and locks shall be furnished by the pump station vendor consistent
with those previously installed.

All panels shall be in NEMA 4 enclosures for outdoor use and the box cover shall have a
hasp for the lock, a flashing red high level alarm light with door. The alarm light shall have
flashing red indication, shall be NEMA 4 rated, shall be oil and water tight, and shall be 1 ½”
diameter.

Panels shall be for 230 volt single phase unless otherwise approved by the Utility
depending upon voltage availability. Control circuit and alarm circuit shall be for 115 volts.

The control panel shall include a schematic wiring diagram permanently posted on the
inside cover of the box. All terminals shall be clearly labeled with proper designation.

The power cable shall be of wire size, run in conduit in accordance with the National
Electrical Code from the panel to the box. A disconnect box shall be located at the building
exterior wall.

Inlet Gasket. Cut the inlet hole and install the inlet gasket at a level between the discharge
level and 1’ above the pump manufacturer(s) recommended alarm level.

Variable Requirements. A check valve shall be installed in the discharge line of each
pumping unit where the static discharge head of the pumping unit is less than 15’ or in
any pumping stations designated by the Utility.

Where field conditions require, or in any pumping station designated by the Utility, a
siphon breaker shall be installed in the discharge line of each pumping unit. Siphon
breakers shall be a minimum of 1 ¼” in size and be approved by the Utility prior to
installation.

10. Duplex Grinder Pump System.

General. Duplex (two pump) grinder pump systems mounted in a fiberglass sewage collection
basin shall be provided as a minimum for each three-family or larger residential unit or commercial
business.

The top of the basin shall be a minimum of 6” below finished floor elevation of the building
it serves and 4” above finished site grade with positive run off grade on all sides. The
basin and pump assembly shall be located a minimum of 10’ from all buildings and water
systems.

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Pumps shall be grinder pumps of the centrifugal type with recessed type impellers and integrally
built-in grinders and submersible motors. Motors shall have seal failure detector and high
temperature shut off. The pumps shall be installed on a lift out rail type system in such a way that
solids are fed in an up-flow direction to the grinder impeller, with no feet, rails, or other obstructions
below the grinder inlet.

Contractor shall submit the manufacturer’s cut sheets and performance specifications to
the Utility prior to purchase.

An isolation valve shall be added at the end of all pressure wastewater mains. A check
valve and isolation valve shall be installed in a vault at all Duplex Pump Stations.

Operating Conditions. The pump shall be capable of operating, without overloading, at any point
on the pump performance curve.

Motor. The motor shall be 5 HP as required and will operate at 1750 or 3450 rpm.

The motor shall be single phase 230 volt, unless otherwise approved by Utility.

The common motor pump and grinder shaft shall be of one piece and shall be 416
stainless steel. The pump impeller and grinder impeller shall thread onto the shaft.

Seal Chamber. The motor shall be protected by two mechanical seals, mounted in tandem, with
an oil filled chamber between the seals for lubricating seal faces. Seal faces shall be carbon
and ceramic lapped to a flatness tolerance of one light band. Metal parts and spring for
seals shall be stainless steel.

Seal Fail Detector. A double electrode shall be mounted in the lower end of seal chamber to
detect any water leakage into the chamber. Electrodes are connected to an amber seal failure
light in the control panel. The seal failure warning system shall not stop the motor but
indicate leakage so that the pump lower seal can be serviced prior to the motor being
damaged.

Pump Impeller. The impeller shall be of the recessed type to provide for an open unobstructed
passage through the volute. The impeller shall be constructed of 85-5-5-5 bronze and shall
have pump out vanes on the back side of the impeller to help keep trash away from seal
and reduce pressure at the seal faces.

Grinder Construction. Grinder assembly shall consist of a grinder impeller and a shredding ring
mounted directly below the pump volute inlet. Grinder impeller shall thread onto shaft and
will be locked with a screw and washer. The shredding ring shall be held in the housing by a
snap ring and steel retaining ring. Both the shredding ring and impeller shall be removable
from the outside without dismantling the pump.

Grinder assembly shall be of such construction that no clearance adjustments are
required when reassembling. The grinder impeller and shredding ring shall be of 440 C
stainless steel and shall be hardened to 58-60 Rockwell.

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Pump and Motor Castings. All castings shall be of high tensile cast iron, shall be treated with
phosphate and chromic rinse and be painted inside and outside with baked on epoxy paint before
machining. Likewise, the interior of the volute shall be coated with baked on epoxy paint.

Power Cords. Motor power cords shall be #14 type ST, four conductor, and motor control cord
to be #16 ST, four conductor. All cord lengths shall be such that no splices will be required
between the pump and control panel. Both cords shall be potted into motor end cap with
epoxy potting compound. In addition, a rubber grommet that seals both cords shall be clamped
on the cords by the end holding cap. Cords shall withstand a pull of 150 pounds without
loosening. The end cap shall have female thread tapping for 1 ½” conduit.

Lift Out Rail System. The Lift Out Rail System shall be furnished as illustrated on the
Utility standard detail drawing.

The lift out rail system must also employ swing type check valves with a bronze
disconnect utilizing an o-ring sealing device. This system shall use a 3/16” stainless steel
lifting chain.

Guide rails shall be 3/4 inch 304 stainless steel installed parallel to one another. Alternate
guide rail systems utilizing other means of disconnect devices are not acceptable.

Level Controls. These controls shall be a non-mercury tube sealed in polyurethane float
and weighted to hold position in the sump. The cord connecting the control shall be SJO
type. Four switches shall be provided; Pump On, Pump Off, High Level Alarm, and Lag On.

Electrical Control Panels General. All panels shall be in NEMA 4 enclosures for outdoor use
and box cover shall have hasp, lock and a flashing red high level alarm light and audible alarm.

Panels shall be for 230 volt single phase unless otherwise approved by the Utility
depending on available voltage. Control circuit and alarm circuit shall be 115 volts.

The following components will be provided for each pump; circuit breaker, magnetic
contactor with 3 leg quick trip ambient compensated overload block, H-O-A switch, green
run light, amber deal fail life, alarm switch for on-off and test connection terminal strip.

Single phase panels shall also have start and run capacitors in addition to a start relay.

The control panel shall have the following options:

(1) Elapsed Time Meter for each Pump
(2) Lightning Arrestor
(3) Phase Monitor in Three Phase Units
(4) Remote Alarm Terminals and Circuitry
(5) Audible Alarm Horn
(6) Mounting Stand for Control Panel

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The control panel shall include a laminated schematic wiring diagram permanently posted
on the inside cover of the box. All terminals will be clearly labeled with proper designation.

Startup. Startup services shall be performed by the authorized factory representative with
Utility personnel observing. Manufacturer shall furnish two operation and maintenance
manuals and parts lists per system.

11. Air and Vacuum Release Valves.

Sewage. All Force Mains and other pressure non-treated mains shall have air and vacuum
release valves installed as they are indicated on the plans. Refer to standard detailed drawings
for additional information. 36” Corrugated piping with appropriate manhole cover may be
substituted when approved by the Utility. The body of these valves shall be conical shaped to
maintain maximum air gap with the spring loaded float and seal plug connection combining to
ensure no contact between the sewage and the seal. The valve shall have a double float design
with the upper float being enclosed in the upper section of the valve and shall be made of
polypropylene. The lower float shall be in the main body of the valve and shall be constructed of
stainless steel. The body shall be constructed of steel, fusion coated inside and out with an epoxy
coating and shall have a funnel shaped lower body to automatically drain sewage back into the
system. All internal metal parts are to be made from corrosion resistant stainless steel with all
operating parts in the upper section to be non-metallic plastic materials. The rolling resilient seal
shall provide smooth positive opening, closing and leak free sealing over the fluctuation of
pressure differentials. The working pressure shall be 230 psi and tested to 460 psi. All hardware
shall be of stainless steel bolts and nuts with plastic washer(s) under the bolt and nut.

The connection on all pipelines shall be the following sizing with an isolation valve of the
same size:

8-inch and smaller 2-inch threaded
10-inch through 16-inch 3-inch flange
18-inch through 24-inch 4-inch flange
30-inch through 48-inch 6-inch flange
54-inch and larger 8-inch flange

All air and vacuum combination release valves shall be model ARI D-020 or approved
equal, automatic air release valves shall be ARI model S-020 or approved equal. All
valves shall be installed in accordance with manufacturer recommendations and shall
have an isolation valve connection for control. All ARV shall have ISO 9002 certification
in order to be supplied on this project.

Pump Station Air Valves. Special application of the air release valves at the pump station piping
shall allow for the ARI model D-040 combination valve. These valves are to be located as shown
on the drawings just past the 900 bend on the header pipe detail. The body/base of these valves
shall be made from high strength lightweight non-corroding fiberglass reinforced nylon and all
operating parts are to be made of engineered corrosion resistance plastic materials. The rolling
resilient seal shall provide smooth positive opening, closing and leak free sealing over the
fluctuation of pressure differentials. The

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valve shall be designed to allow larger than normal automatic orifice providing efficient air
release and minimize potential debris build-up and clogging. The working pressure shall
be 200 psi and shall have a 2” threaded connection. All air and vacuum release valves
shall be model ARI D-040 or approved equal. The connection to the system shall be a
direct threaded connection on the top of the pipe with a saddle and an isolation valve.

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ARTICLE II. WASTEWATER CONSTRUCTION METHODS

1. Construction Methods - General.

This section of the specification(s) shall govern the construction procedures used in the
installation of sanitary wastewater facilities under the jurisdiction of The City of Hot
Springs. Construction procedures other than those outlined in this specification(s) require
proper approval of The City of Hot Springs. Complete specifications covering any unusual
or special construction procedures shall be submitted for approval, said approval must be
received prior to beginning any construction operations.

2. Excavation, Bedding, and Backfilling.

General. Excavation shall include the removal, handling, re-handling, refill or backfilling and
disposal of any and all materials encountered in the work. It shall also include all pumping,
drainage and shoring. The excavation activities shall also include the responsibility of
added expenses or other liability that may arise from obstacles or conditions, foreseen or
unforeseen that may be encountered in the work.

All excavation necessary for laying pipe, constructing manholes, etc., shall be made to line and
grade as indicated on the plans and as specified herein. Trenches shall be excavated to the
alignment and depth required and shall not advance more than 100’ in advance of the completed
pipe unless otherwise permitted by the Engineer. The trench shall be braced and drained
as may be required to ensure that workmen may work therein safely and efficiently in
accordance with OSHA regulations. All excavation(s) shall be open cuts with vertical
sides except in special cases where the Engineer may permit sloping sides above a point
2’ above the top of the pipe or except where tunneling is required. All excavation shall be
made in such manner and to such widths as will give ample room for properly laying and
inspecting the pipes.

Since rock may vary from cobbles to hard rock and from easily ripped shale to sandstone
(which may require blasting) the Contractor shall follow the standard details for trench
design, bedding and backfill. The Contractor will also make his own determination of rock
quantities and construction techniques.

The maximum width of trench for wastewater pipe installation at a point 2’ above the top
of the pipe shall be the external diameter of the barrel of the pipe plus sufficient space to
ensure backfill material is placed in accordance with applicable standards and
specification(s).

The Engineer and/or Utility shall, at any time, have the authority to require the Contractor to
discontinue the use of any excavation machine or other equipment which, in his judgment, is not
adapted to the purpose for which it is used.

All excavation(s) shall be dewatered before any construction begins. Concrete shall be
placed only upon dry, firm foundation material and pipe shall be laid only in properly prepared
trenches. All pipe ends shall be closed using devices or materials approved by the City of Hot

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Springs at the end of each day's operation. Dewatering shall be necessary to avoid interfering
with the progression of the work or endanger adjoining property and structures. The Contractor
shall maintain all excavation(s) in good order during the construction, so as not to hinder or impact
the pipe laying, masonry or other work. The Contractor shall take all reasonable precautions
to prevent movement of the sides of such excavation and shall remove at his own expense any
material sliding into the excavation.

The Contractor shall furnish and put in place such shoring as may be required to support
the sides of all trenches or other excavations. This shoring will not be considered as a
separate pay item.

Wherever necessary for protection of workmen, for security of adjacent Utilities,
structures, for stability of trench, for proper installation and operation of wastewater pipe
the Engineer shall have the right to require that the excavation be braced and rendered
secure to his satisfaction.

All material excavated shall be placed so as to not interfere with public travel to the extent
possible. At street crossings and other points, as may be directed by the Engineer, the
trenches shall be bridged in a proper and secure manner so as to prevent any serious interruption
of travel upon the roadway or sidewalk. This will also provide access to particular public premises.

Surplus excavated material(s), other than those utilized to achieve final grade in
accordance with the drawings shall be disposed of by the Contractor.

Excavation - Trench Sewage Force Mains. Trenches for force mains shall be of the width
and depth necessary to enable the proper installation of the pipe. All pipe lines shall be
laid in trenches of such depth as to provide a minimum cover of 30" over the top of pipe barrel
unless otherwise indicated on the plans.

Width of pipe trench for sewage Force Mains shall be adequate for the installation of the
pipe and make-up of joints, however, in no case shall the width of the trench at the top of the
pipe be wider than the outside diameter of the pipe plus two feet.

The bottom of the trench shall be accurately graded so that the pipe will be in continuous
and uniform contact with and have a longitudinal bearing on undisturbed soil for the full
length of the barrel of the pipe. The trench bottom shall be excavated by hand below the
bell ends so that the bell does not bear on the trench bottom.

If the soil at the bottom of the trench or the subgrade is too soft to properly support the
pipe, the Contractor shall excavate below the lower extremity of the pipe as directed by the
Engineer, and place select material. Said select material shall be thoroughly tamped into place
to receive the pipe.

Excavation - Trench for Gravity Wastewater Pipe. All pipe lines shall be laid in trenches of such
depth as to provide a minimum cover of 30" over the top of pipe barrel unless otherwise
indicated on the Plans.
In order to avoid superimposed loading in excess of the designed and specified pipe strength

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and to provide sufficient room for proper installation and bedding of wastewater pipe, the trench
widths for the pipe sizes used shall be kept within the limits specified as follows:

Inside Pipe Maximum Width of Maximum Width of Trench 12”
Trench at Top of Pipe
Diameter Above Outside Top of Pipe
2' - 6"
6" 2' - 6" 2' – 10"
8” 2' – 10"
10” 2' - 6" 3’ – 0”
12” 3’ – 0” 3’ – 4”
14” 3’ – 0” 3’ – 6”
15” 3’ – 0” 3’ – 6”
16” 3’ – 0” 3’ – 6”
18” 3’ – 6” 4’ – 0”
21” 3’ – 6” 4’ – 4”
24” 4’ – 0” 4’ – 8”
27” 4’ – 0” 5’ – 0”
30” 4’ – 6” 5’ – 6”

If it becomes necessary to reduce the earth load on the trench banks to prevent sliding
and cave-ins, it will be permissible to cut the trench banks on a slope above an elevation
2’ above the outside top of the pipe. Under no circumstances, however, shall the specified
maximum width 12” above the outside top of the pipe be exceeded, except at points where
the combined superimposed earth and live loads on the pipe are sufficiently low to permit
an increase in the specified maximum trench width, and then only where such an increase
in trench width is authorized by the Engineer.

Shaping of the trench bottom and bedding procedures shall be as specified in this section.
Under certain conditions, excavation below the planned invert of the pipe will be required
before preparation of the bedding has begun, as listed in the following paragraphs:

If the soil at the bottom of the trench is in such condition that it cannot be properly shaped
and graded, if the subgrade material is too soft to properly support the pipe the Contractor
shall excavate below the normal subgrade elevation as directed by the Engineer.
Whenever excavation is carried below the specified subgrade, at the direction of the
Engineer, the Contractor shall provide and install a fill of Class II bedding thoroughly
tamped into place up to an elevation sufficient to prepare the subgrade as specified in
this section for the particular classification of bedding that may be required.

Where water occurs in trenches they shall be excavated to a depth of approximately 6” below
grade and backfilled with gravel to a point approximately 1/6 of the internal pipe diameter or 2",
whichever is the greater, above grade.

Pumps shall then be kept operating, taking suction out of a sump below the gravel so as to
hold the water level well below the bottom of the pipe until the joints have been placed and firmly
bedded in position.

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Excavation(s) for manholes and other accessories shall be sufficient to leave at least 12”
of clear space between their outer surfaces and the embankment or timber which may be
used to protect them.

Disposal of Excavated Materials. Excavated material(s) shall be stockpiled adjacent to the
work, they will be used for backfilling as required. Excavated material(s) which is unsuitable for
backfilling, excess material(s) and all excavated material(s) from a street cut shall be
removed from the site and disposed of in a manner approved by the Engineer.

Use of Explosives. In the event the use of explosives is necessary for the efficient prosecution
of the work the Contractor shall notify the Engineer in advance of their use and shall exercise
every precaution to prevent damage to adjoining improvements or property. Any damage to
private property resulting from the use of explosives shall be the liability of the Contractor.
In all cases where the explosives are necessary a permit from the local governmental
agency shall be obtained by the Contractor prior to their use.

Bedding, Embedment, and Backfilling of Wastewater Lines. No backfilling of trenches shall
be performed until the pipework to be covered has been inspected by the Engineer. When any
shoring is withdrawn, as backfilling progresses, all voids or spaces left thereby shall be carefully
and thoroughly filled and then compacted with properly shaped tools.

The Engineer shall have the right to forbid the use of any compacting tools or machines
that he considers dangerous to the pipe or incapable of properly compacting the backfill.

All backfill compacting operations shall be accomplished in the presence of the Engineer,
these operations shall proceed in such sequence as he may direct. The Contractor shall
be responsible for the stability of all backfill made under the contract until final acceptance of
the work. The Contractor shall also bear the expense of replacing any portions which
have become displaced due to carelessness or negligent work on the part of the
Contractor, damages resulting from natural causes, such as a storm, and not attributable,
in the opinion of the Engineer, to unavoidable movements of the ground upon which the
backfill is made.

Backfilling of trenches for pipe wastewater shall start as soon as the Engineer considers
the joints to be satisfactory. Backfill material(s), as required in the standard details and in
these specification(s) shall be carefully placed in the trench so as not to move the pipe or
dislodge any of the jointing material(s). In areas to be paved, trench backfill should be full depth
compacted Class 7 base. Material(s) will be thoroughly but carefully placed under and
around the pipe up to a point 12" above the top of the pipe. The utmost care shall be taken
not to disturb the pipe or to shift a pipe from its proper position by careless or unskilled
ramming around it or by unequal filling on the sides.

Where a trench is in highway or street pavement, backfill for the balance of the trench,
above a point one foot above the top of the sewer shall be compacted by placing in layers
of not more than 12” thickness. Material(s) will then be compacted with mechanical
tampers or by satisfactory method(s) that will obtain the density hereinafter specified unless
a specific method is provided by the special provisions. The density of compacted material in

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