A.
Sanitary sewer gravity mains and force mains.
(1)
No gravity sewer conveying raw sewage shall be less than eight inches
in diameter.
(2)
Sanitary sewer mains shall not be installed under either curbs or
sidewalks. In addition, trays, cleanouts and force main valves shall
not be installed under or in concrete cement.
(3)
No underdrains, conduits and/or cables of any nature will be installed
in the same trench with sanitary sewer.
(4)
PVC or DIP gravity sewer and force mains shall be used for all sanitary
sewer except the following conditions which include, but are not limited
to:
(5)
Sewer and water mains generally should be separated a distance of
at least 10 feet horizontally. If such lateral separations are not
possible, the pipes shall be in separate trenches with the sewer at
least 18 inches below the water main; or such other separation as
approved by the owner.
(6)
Concrete encasement will be required for the following conditions:
(a)
At all locations where a proposed sanitary sewer main is located
closer than 10 feet to a water main (measured horizontally).
(b)
At all crossings of sanitary sewer lines and water lines where
the vertical separation is less than 18 inches.
(c)
At all crossings of sanitary sewer lines and water lines where
the sanitary sewer is vertically above the water line.
(d)
All other locations where the vertical or horizontal separation
between proposed and existing utility pipes is less than 18 inches.
(7)
When a new sanitary line is constructed and tied into an active manhole,
the new line will be plugged and remained plugged until all testing
has been completed and approved by the owner.
(8)
All sanitary sewer laterals that are scheduled for connection to
a specific sewer main must be connected and extended to the curbline
prior to the acceptance testing on that line.
(9)
Neither repair clamps nor saddles are permitted to be used on new
sanitary sewers within the jurisdiction of the owner. These are only
to be used in cases of emergency, and then only with the prior written
approval of the owner. If and when saddles are approved, they will
be of the strap-on type with stainless steel hardware; no bolt-on
saddles will be permitted.
(10)
Force mains will not be tied directly into a gravity manhole.
A collector manhole will be constructed adjacent to the gravity manhole
and the force main will terminate in this collector manhole. The effluent
will flow by gravity into the manhole, which is part of the gravity
system.
(11)
Private ejector lines shall be connected directly to the sewer
main.
(12)
Air relief valves will be required at the high points of any
force main.
(13)
Interceptors shall be provided for commercial and industrial
discharges when in the opinion of the owner and/or Engineer they are
necessary for the proper handling of liquid waste containing grease,
oil, sand or lint to the building drainage system, the public sewer
or sewage treatment plant or processes. All commercial and industrial
dischargers must complete a usage questionnaire that requires submittal
of plumbing plans for each facility.
B.
Minimum grades and velocity of flow.
(1)
All sewer shall be designed and constructed to give mean velocities,
when flowing full, of not less than 2.0 feet per second, based on
Kutter's Formula using an "N" value of 0.013 for ductile iron pipe
or an "N" value of 0.01 for PVC pipe.
(a)
The following are the minimum slopes that should be provided;
however, slopes greater than these are desirable:
|
Minimum Slope in Feet per 100 Feet
| ||
|---|---|---|
|
Sewer Size
|
Ductile Iron
|
PVC
|
|
8-inch
|
0.40
|
0.30
|
|
10-inch
|
0.28
|
0.20
|
|
12-inch
|
0.22
|
0.15
|
|
15-inch
|
0.15
|
0.10
|
|
18-inch
|
0.12
|
0.075
|
|
21-inch
|
0.10
|
0.06
|
|
24-inch or above
|
0.08
|
0.05
|
(b)
Minimum slope of mains emanating from terminal manholes shall
be increased where flow conditions exist. Cul-de-sac lots shall provide
minimum 0.80% slope to terminal manhole.
(2)
Slopes slightly less than those required for the 2.0 feet per second
velocity, when flowing full, may be permitted. Such decreased slopes
will only be considered where the depth of flow will be 0.3 of the
diameter or greater for design average flow. Whenever such decreased
slopes are selected, the design engineer must furnish with his report
his computations of the anticipated flow velocities of average and
daily or weekly peak flow rates. The pipe diameter and slope shall
be selected to obtain the greatest practical velocities to minimize
settling problems.
(3)
Sewers shall be laid with uniform slope between manholes.
(4)
Where velocities greater than 15 feet per second are attained, special
provision shall be made to protect against displacement by erosion
and shock.
(5)
The use of sewers with a slope in excess of 20% is prohibited. Instead,
drop manholes should be considered. In any event, the owner and its
Engineer will review all proposed sewers with a slope in excess of
20% on a case-by-case basis.
C.
Alignment. All sewers 24 inches or less shall be laid with straight
alignment between manholes. The alignment shall be checked by either
using a laser beam or lamping.
D.
Changes in pipe size. When a smaller sewer joins a larger one, the
invert of the larger sewer should be lowered sufficiently to maintain
the same energy gradient. An approximate method for securing these
results is to place the 0.8 depth point of both sewers at the same
elevation.
E.
Manholes.
(1)
Manholes shall be installed at the end of each line; at all changes
in grades, alignment or size, and at distances not greater than 400
feet.
(2)
A drop pipe should be provided for a sewer entering a manhole at
an elevation of 24 inches or more above the manhole. Drop manholes
shall be constructed with an outside drop connection. The entire outside
of the drop connection shall be encased in concrete.
(3)
The minimum diameter of manholes shall be 48 inches. A minimum access
diameter of 30 inches shall be provided.
(4)
The flow channel through manholes should be made to conform in shape
and slope to that of the sewers.
(5)
"SANITARY SEWER" shall be cast in lids of all sanitary manholes.
(6)
All pipe penetrations into a manhole shall be no less than 90°
to the center line of the downstream main.
(7)
Manhole rims shall be set at base paving elevation and adjusted at
a later date prior to installing the surface course. Manholes located
in grassed areas shall be raised three inches above grade with fill
built-up around the cover.
F.
Inverted siphons (if approved by the Engineer).
(1)
Inverted siphons should not have less than two barrels, with a minimum
pipe size of six inches and shall be provided with the necessary appurtenances
for convenient flushing and maintenance.
(2)
Sufficient head shall be provided and pipe sizes selected to secure
velocities of at least 3.0 feet per second for average flows.
(3)
The inlet and outlet details shall be so arranged that the normal
flow is diverted to one barrel, and that either barrel may be cut
out of service for cleaning.
G.
Laterals.
(1)
All laterals are to be connected to the main by means of a wye connection only. The standard lateral connection will be four inches, or six inches in the case of PVC. All service laterals will be laid with the same care prescribed in § 51-12 of these specifications, which includes proper trench construction and backfill, and stoning of the trench bottom when necessary to obtain a stable base under the pipe.
(2)
The standard sewer service lateral will be constructed of PVC, cast
iron, ductile iron or a combination thereof. If the owner or builder
desires to use pipe of a material other than that listed above, he
must obtain the prior written approval of the owner.
(3)
Adapters to connect the service lateral to house service lateral
must be approved by the owner.
(4)
The standard gravity sewer lateral will be constructed of four-inch
diameter for all residential or six-inch diameter for commercial/industrial.
Material shall be PVC SDR 35 pipe from the sewer main to the cleanout
just behind the curbline.
(5)
All sanitary sewer laterals should be installed at a grade equal
to 1/4 inch per foot, but in no case will they be installed at a grade
less than 1/8 inch per foot.
(6)
All laterals will be installed at a constant grade and in a straight
line. There will be a cleanout constructed and a plug provided just
behind the curbline and at any point where it is necessary to change
the direction of the lateral. Cleanouts are required every 50 feet
on long laterals.
(7)
When the sanitary sewer mains are over eight feet in depth, the construction
of a deep cut lateral is required.
(8)
Minimum depth for a sanitary sewer lateral is 36 inches at the curbline.
(9)
In no case shall laterals be installed under driveways. A lateral
location plan shall be submitted to the owner.
H.
Lateral connection to existing lines.
(1)
Gravity. Connections of the saddle type installed in the main sewer
line shall be made in a smooth, round hole, machine-drilled into the
top quarter of the main sewer pipe. The fitting should be such to
insure that no protrusion of the fitting into the main sewer pipe
shall result. The fitting shall conform to the contour of the sanitary
sewer and is one that is specifically designed to fit the particular
size main sewer pipe into which the connection is made. The machine-drilled
hole shall be of such size to provide 1/8 space between the shoulder
of the fitting and the face of the main sewer pipe when installing.
All voids shall be completely filled with joint material. The joint
material shall be completely waterproof and capable of withstanding
the stresses normally encountered in construction or maintenance.
All saddles shall be a double strapped stainless steel connection.
Wrap saddle in six mil clean polyethylene and encase in minimum six
inches of concrete.
(2)
Sewage ejectors:
(a)
Sewage ejectors discharging to an existing gravity sewer shall be provided with a check valve and shutoff valve at the location of the ejector pump. The connection to the main shall be the same as in Subsection H(1), Gravity.
(b)
Sewage ejectors discharging to a force main shall be connected
via a direct tap. Each connection shall be equipped with a check valve
and shutoff valve in an at-grade box at the property line and a second
check valve and shut off valve at the location of the ejector pump.
I.
Force main connection to existing force main. Sewage ejectors discharging
to existing force mains shall be designed to overcome the total static
and dynamic head conditions in the force main when flowing full. Connections
shall be done with a tapping sleeve in accordance with manufacturer's
directions.
J.
Grease recovery units and interceptors.
(1)
Grease recovery units (GRU) shall be installed in the waste line(s)
leading from sinks, drains, or other fixtures in all food service,
food processing, or other commercial establishments which produce
grease/oil and which are connected into the public sewer system. Greases
and oils are defined as any substance(s) with physical characteristics
which enable them to be quantitatively analyzed based upon their solubility
in Freon, including hydrocarbons, fatty acids, soaps, fats, waxes,
oils and any other substances or materials not volatilized during
solubility testing. All grease recovery units must be constructed
of stainless steel or reinforced concrete. The owner shall approve
the size, type, and location of each recovery unit. A sediment/solids
removal unit must be installed before the grease removal unit. All
installations must conform to the manufacturer's specifications and
to all applicable building codes. For new construction, all grease
interceptors shall be an exterior concrete unit.
(2)
Oil, sand and lint interceptors shall be installed in the waste line(s)
of all commercial establishments which produce such waste and are
connected into the owner's sewer system.
(3)
All grease recovery units or interceptors shall be so installed as
to provide ready accessibility to the cover and contents thereof,
for servicing and maintaining the grease recovery units or interceptors
in working operating condition. All grease recovery units or interceptors
shall be maintained in an efficient operating condition by regular,
periodic removal of accumulated contents.
(4)
The owner, through its authorized officers, employees and agents,
shall have authority to inspect, at reasonable times, those food service,
food processing or other commercial establishments which produce oil,
grease, sand, lint or other harmful ingredients and which are connected
into the owner's sewer system to ensure that said establishments which
produce oil, grease, and are properly maintaining their grease recovery
unit and/or interceptor on all waste line(s).
(5)
Plumbing and floor plans shall be submitted for owner review and
approval. Finalized plans shall be forwarded by the establishment
to the owner for their records.
(6)
Full service restaurants, pizzerias and fast food type restaurants
or other commercial establishments which produce excessive quantities
of grease/oily waste shall furnish both an interior GRU and an exterior
grease trap.
(7)
Grease conveying laterals shall be separated from laterals conveying
raw sewage until after interceptor connection.
K.
Prior to construction. Prior to starting construction of a sewer
system within the Township, the developer or owner must have in his
possession a set of owner-approved drawings. In addition, he must
have paid all the necessary charges and fees as well as obtaining
the necessary bonding. When easements are necessary, all paperwork
must be in order; and if road-opening permits are required, these
must also be obtained before work can begin.
A.
Description. PVC gravity sewer and pressure pipe for proposed sanitary
sewer system.
B.
Materials.
(1)
(2)
PVC pressure sewer pipe and fittings:
(a)
AWWA C900; sizes four-inch through 12 inches.
[1]
Coupling shall be an integral part of pipe.
[2]
Pipe shall have slip-on joints with a rubber ring seal.
[3]
Pipe shall be PVC "Blue Brute" pipe with "Ring-Tite" joints
as manufactured by Johns-Manville, or approved equivalent.
[5]
Fittings and rubber rings shall be as supplied by the pipe manufacturer.
(3)
Locator wire.
(a)
Locator wire shall be minimum No. 9 AWG suitable for direct
burial rated at 600 VAC.
(b)
Locator wire shall be placed on the top side of the HDPE pipe.
Wire shall be attached to the pipe using nylon cable ties spaced at
ten-foot intervals.
(c)
Locator wire shall be continuous along entire length of pipe.
Heat shrink splice kits shall be used where wire sections need to
be spliced.
(d)
Locator wire ends shall be terminated at the valve box and curb
stop pit using a copper set screw lug attached to the valve box and
the curb stop pit.
C.
Methods of construction.
(1)
Reference standard used in this specification section:
(a)
American Society for Testing and Materials (ASTM):
[1]
ASTM D-3034: Type PSM Polyvinyl Chloride (PVC) Sewer Pipe and
Fittings.
[2]
ASTM F-679: PVC Large Diameter Plastic Gravity Sewer Pipe and
Fittings.
[3]
ASTM F-794: PVC Large Diameter Ribbed Gravity Sewer Pipe and
Fittings.
[4]
ASTM D-3212: Joint for Drain and Sewer Plastic Pipes Using Flexible
Elastomeric Seals.
[5]
ASTM D-2241: PVC Plastic Pipe.
(b)
American Association of State Highway and Transportation Officials:
[1]
M-45: Aggregate for Masonry Mortar.
(c)
New Jersey Department of Transportation, Standard Specifications
for Road and Bridge Construction 1980 Supplement.
(3)
Product delivery, storage and handling:
(a)
Storage of materials:
[1]
Store materials to prevent physical damage.
[2]
Store pipe and fittings off ground to prevent dirt and debris
from entering.
[3]
Store flexible gasket materials and joint primer or adhesive
compounds in cool dry place. Keep rubber gaskets clean, away from
oil, grease, excessive heat, and out of direct rays of sun.
(b)
Handling of materials:
[1]
Protect materials during transportation and installation to
avoid physical damage.
[2]
Use extra care in cold weather when flexibility and impact resistance
of PVC pipe is reduced.
[3]
Do not install out-of-round pipe.
[4]
Unload pipe to prevent abrasion.
[5]
Do not drag or push pipe when handling or distributing on project
site.
(4)
Inspection by contractor:
(c)
Inspect pipe for defects prior to placement in trench. The pipe
and fittings shall be free from visible cracks, holes, foreign inclusions
or other injurious defects.
(d)
Assure that all materials are to the type specified and are
not defective. Unmarked pipe; or pipe and materials not meeting specifications
requirements shall be removed from the site as directed by the Engineer.
(5)
Excavation for trenches:
(a)
Dig trenches to the uniform width required for the particular
item to be installed, sufficiently wide to provide ample working room.
(b)
Excavate trenches to the depth indicated or required. Carry
the depth of trenches for piping to establish the indicated flow lines
and invert elevations.
(c)
Trenches for pipes shall not be opened more than the number
of linear feet of pipe that can be placed and backfilled in one day.
(d)
Grub roots and stumps within six inches of outside surface of
pipe bottom and sides to minimum depth of six inches below bottom
of trench.
(e)
Install pipe bedding of material approved for initial backfill
in accordance with the standard details and as specified herein.
(6)
Installation:
(a)
Lay pipe only in presence of Engineer, Engineer may order removal
and relaying of pipe not so laid.
(b)
Fine grade trench bottom so that pipe is supported for its full
length.
(c)
Lay pipe to lines and grades required. Face socket end of pipe
in direction of pipe laying.
(d)
Do not lay pipe on unsuitable material, in wet trench, or in
same trench with another pipe or utility.
(e)
Lower pipe into trench with ropes, machinery, or other means
approved by Engineer.
(f)
General procedure for joining pipe:
[1]
Do not use excavating equipment to shove pipe sections together.
[2]
Hold pipe securely and in proper alignment when joining.
[3]
Do not disturb previously made joints. Check completed piping
to assure joints are intact. Ensure placement of backfill over pipe
is accomplished without disturbing pipe position.
[4]
Do not allow earth, stones, or other debris to enter pipe or
fittings.
[5]
Method of installing joint materials and joining piping shall
be in strict accordance with manufacturer's printed instructions as
approved by the Engineer.
(7)
Backfill and compaction:
(a)
Initial backfill:
[1]
Initial backfill material shall be soil aggregate designation
I-8 conforming to the requirements of Article 8.8.1. Table 36 of the
Standard Specifications, 1980 Supplement, or stone crushing to conform
with AASHTO designation M-43 (ASTM designation D448), Size No. 8,
1/8 inch to 3/8 inch (2.36 mm to 9.25 mm) clean, free flowing and
shall meet all ASTM C-33 requirements for quality and soundness.
[2]
Install initial backfill material as shown on the standard details
for the type of pipe being used.
[3]
When required material shall be placed under the pipe haunch
to provide adequate side support. Material shall be installed entire
trench width and shall be tamped and rodded to ensure full contact
with pipe at haunch up to the spring line.
[4]
Little or no tamping of the initial backfill directly over the
pipe shall be done.
(8)
Testing:
(a)
Deflection testing:
(b)
Lamping:
[1]
Engineer will lamp all installed pipe between manholes. Sewer
lines shall meet the following standards to pass the lamping inspection.
(c)
Air testing:
[1]
Air testing shall conform to the requirements of § 51-17, Testing sanitary sewer force mains, except as herein modified.
[2]
The minimum time duration for a low-pressure exfiltration pressure
drop between two consecutive manholes shall not be less than shown
in Table 1.
[3]
The prescribed drop shall not exceed 0.5 psi from 3.5 to 3.0
psi in excess of the groundwater pressure above the top of the sewer.
|
Table I
Minimum Duration For Air Test Pressure Drop
| ||
|---|---|---|
|
Pipe Size
|
Time
(minutes)
| |
|
Inches
|
Millimeters
| |
|
4
|
100
|
2 1/2
|
|
6
|
150
|
4
|
|
8
|
200
|
5
|
|
10
|
225
|
6 1/2
|
|
12
|
305
|
7 1/2
|
|
15
|
380
|
9 1/2
|
A.
Description. Provide ductile iron pipe for sanitary sewer force main
or for gravity sanitary sewer main.
B.
Materials.
(1)
Sanitary sewer force main:
(b)
Joints for ductile iron pipe: push-on joint, conforming to AWWA
C151 and AWWA C111.
(d)
Plugs and clamps. Plugs shall be solid plugs conforming to the
pipe sizes indicated on the plans, and shall be Plug No. F-1147 as
manufactured by Clow Corporation, or approved equal. Clamps for retaining
plugs shall be Socket Clamp No. F-740, as manufactured by Clow Corporation,
or approved equal.
(2)
Sanitary sewer gravity main:
(b)
Joints for ductile iron pipe: push-on joint, conforming to AWWA
C151 and AWWA C111.
(d)
Plugs and clamps: Plugs shall be solid plugs conforming to the
pipe sizes indicated on the plans, and shall be Plug No. F-1147 as
manufactured by Clow Corporation, or approved equal. Clamps for retaining
plugs shall be Socket Clamp No. F-740, as manufactured by Clow Corporation,
or approved equal.
C.
Methods of construction.
(1)
Submittals:
(a)
All pipe and fittings shall be inspected and tested at place
of manufacture as required by the AWWA standards referenced in this
specification. Provide Engineer with two copies of certifications
from each manufacturer stating the product was inspected as required,
and that the test results comply with the AWWA standards.
(c)
All manufacturers shall validate other than by certification
the ductility of each length of pipe by an Underwriters Laboratory
approved method. All ductile iron pipe is to have Underwriters Laboratory
approval.
(d)
Submit all test results, including a diagram of sections tested.
(2)
Inspection and quality of pipe:
(a)
Before being lowered into the trench, each pipe shall be carefully
inspected, and those not meeting the specifications shall be rejected
and either destroyed or removed from the work within 10 hours. No
pipe shall be laid except in the presence of the Engineer or his authorized
inspector. The Engineer may order the removal and relaying of any
pipe not so laid.
(b)
In addition to the inspection made by the Engineer, the contractor
shall carefully examine all pipe and special castings before placing
the same in the trench. Any pieces which are broken or show evidence
of cracks or fractures shall be rejected by him. Such inspection shall
carry with it the responsibility on the part of the contractor for
the removal at his own expense of all pipe, special castings, and
appurtenances, incorporated in the work, and which under test are
found to be cracked or otherwise defective.
(3)
Installation of pipe and fittings:
(a)
Excavation and backfill for pipes shall conform to § 51-8, Trench excavating, backfilling and compacting.
(b)
All piping shall be installed in a neat and workmanlike manner.
All piping shall be installed to accurate lines and grades and shall
be supported as shown in the standard details, specified, or necessary.
Where temporary supports are used, they shall be sufficiently rigid
to prevent shifting or distortion of the pipe. Suitable provision
shall be made for expansion where necessary.
(c)
No defective pipe or fitting shall be laid or placed in the
piping, and any piece discovered to be defective after having been
laid shall be removed and replaced by a sound and satisfactory piece
by the contractor.
(d)
Every pipe and fitting shall be cleared of all dirt and other
debris before being installed and shall be kept clean until accepted
in the completed work.
(e)
No pipes shall be laid in fill or other unstable material, in
wet trench, or in same trench with another pipe or other utility.
A minimum eighteen-inch clearance shall be maintained between the
outside surface of pipe and outside surface of other existing pipes
and structures. When this clearance cannot be maintained, contact
the Engineer for instructions prior to proceeding with the pipe installation.
(f)
No direct contact between pipes and structures at crossings
will be permitted. Pipes in place shall not be worked over or walked
on until covered by layers of earth well tamped in place to a depth
of 12 inches over the pipe.
(g)
Minimum cover over sewer mains shall be four feet.
(h)
The interior of all pipes shall be thoroughly cleaned of all
foreign material before being lowered into trench. Pipes shall be
kept clean during laying operations by means of plugs or other approved
methods.
(i)
Brace all plugs as required to prevent leakage or blowout during
testing.
(4)
Piping supports for ductile iron force mains. The contractor shall
furnish and install all supports necessary to hold the piping and
appurtenances in firm, substantial manner at the lines and grades
required. Where required, bends, tees, and other fittings buried in
the ground shall be backed up with concrete placed against undisturbed
earth where firm support can be obtained. If the soil does not provide
firm support, then suitable bridle rods, clamps, and accessories to
brace the fitting properly shall be provided. Such bridle rods, etc.,
shall be coated thoroughly with an approved bituminous paint after
assembly or, if necessary, before assembly. This work shall include
bracing plugs to prevent leakage or blowout during testing.
(5)
Handling and cutting pipe. Every care shall be taken in the handling
and laying of pipe and fittings to avoid damage to the pipe, scratching
or marring machined surfaces, and abrasion of the coating or lining.
Pipe cuts shall be made using an abrasive wheel, rotary wheel cutter,
guillotine pipe saw, milling wheel saw, oxyacetylene torch or other
method approved by the Engineer. Ground cut ends and rough edges smooth.
For push-on connections, bevel all cut ends.
(6)
Assembling piping.
(a)
Clean ring groove and bell socket prior to inserting rubber
gasket scal. Properly seat gasket; make sure it faces proper direction.
(b)
Clean and lubricate spigot end of pipe. Lubricate spigot end
of pipe and rubber gasket.
(c)
Hold pipe securely and in proper alignment when joining.
(d)
Join pipe so that reference mark on spigot end, if provided
by manufacturer, is flush with end of bell.
(e)
Join pipe in strict accordance with manufacturer's printed installation
procedures.
(7)
Protection of work:
(a)
Great care shall be exercised in the protection of finished
work. Joints once made and disturbed shall be subjected to immediate
rejection. It shall, therefore, be the duty of the contractor to avoid
the slightest movement in completed work, while in the act of laying
the pipe, in backfilling, or in the passage of workmen up and down
the trench. At all times during which pipe is not laid, the end of
the pipe shall be sealed with a tight-fitting plug. In no case will
the drainage of trench water through a complete pipe be permitted.
(b)
All curves, bends, tees, hydrants or ends of pipe shall be securely
blocked with socket clamps or yokes to prevent movement. At the end
of line or turn, where provision has been made for future extension
or connection, fittings shall be furnished with lugs and anchored
by means of socket clamps or yokes.
(8)
Adapters. When it is necessary to join pipes of different types the
contractor shall furnish and install the necessary adapters. Adapters
shall have ends conforming to the above specifications for the appropriate
type of joint to receive the adjoining pipe. When adapters join two
classes of pipe, the bodies may be of the lighter class.
(9)
Pipe repairs shall be accomplished utilizing stainless steel double
banded repair clamps (Rockwell 226 "Super Reach" or equal), installed
in accordance with the manufacturer's printed instructions.
B.
Materials.
(1)
Precast concrete manholes shall conform to ASTM C 478.
(2)
Rubber gasket for precast manhole sections shall conform to ASTM
C 361. Concrete and rubber gasket joint shall be watertight at head
pressure of up to 50 feet.
(4)
Ladder rungs. Shall be aluminum alloy conforming to ASTM C478.
(a)
Steps shall be 12 inches wide with a nonslip surface, with the
ends turned up a minimum of two inches. Rungs shall be set into the
wall a minimum of three inches, and extend six inches from the manhole
wall.
(5)
Castings for manholes. Campbell Foundry Pattern No. 1012D with lifting
handles and pick holes and "SANITARY SEWER" cast in lid, or approved
equal.
C.
Methods of construction.
(2)
Reference standards used in this specification:
(a)
New Jersey State Highway Department Standard Specifications:
|
Section 603: Inlets and Manholes.
|
(3)
The general method of construction and manhole reconstruction shall
conform to Section 603 of the Standard Specifications. The manhole
shall be constructed as shown on the standard details.
(4)
Manhole walls shall be constructed of precast concrete rings and
all joints between. The outside surface shall be painted with seal
coats of coal tar or asphalt. Manhole walls may be constructed of
poured concrete, subject to approval by the owner's Engineer. Installation
of rubber gaskets for precast manholes shall be in accordance with
the manufacturers' recommendations.
(5)
Frames shall be well bedded in mortar, making a watertight joint.
Cover and frame shall have a shop coat of asphaltic pitch and shall
have a field coat of similar paint after the frame is set in the final
position. Steps shall be provided in the manhole as shown on the standard
details.
(6)
Each manhole shall be constructed absolutely watertight. Manholes
that are not watertight will not be accepted. Plastering on top of
defective joints to correct leaky conditions will not be permitted.
(7)
The invert channels shall be smooth and semicircular in shape conforming
to the inside of the adjacent sewer section. Changes in direction
of flow shall be made with a smooth curve of as large a radius as
the size of the manhole will permit. Changes in size and grade of
the channels shall be made gradually and evenly. The invert channels
shall be formed in the concrete fill above the manhole base, or shall
be half tile laid in concrete, or shall be constructed by laying full
section sewer pipe through the manhole and cutting out the top half
after the surrounding concrete has hardened. The floor of the manhole
outside the channels shall be smooth and shall slope toward the channels
not less than one inch per foot nor more than two inches per foot.
(8)
Construct manholes to the lines and grades required in the system
being installed.
(9)
A maximum of four courses of brick, up to 12 inches in height, shall
be used on any precast manhole. When a greater number of courses are
required to attain the proper grade, another precast section shall
be used.
(10)
Provide all manhole top sections with minimum thirty-two-inch
diameter clear opening.
B.
C.
Pumps.
(1)
Pumping station capacity should be compatible with the ultimate capacity
of the influent sewer. At least two pumps, each designed to handle
peak flows for ten years hence, shall be provided. If more than two
pumps are provided, their capacities shall be such that, upon failure
of the largest pump, the others will handle such peak flows. Pumps
shall include run-hour meters on the main electrical panels.
(2)
Special repair tools and accessories as well as 10 copies of all
operation and maintenance literature required for maintenance shall
be provided.
D.
Wet wells.
(1)
The capacity of a wet well should not exceed 10 minutes retention
when flow is at the average dry weather rate.
(2)
The floors of wet wells shall slope at least 45° toward pump
suctions to prevent solids accumulation.
(3)
Wet wells shall be designed and installed to comply with OSHA regulations
and the requirements governing confined space entry.
E.
Electrical equipment.
(1)
All control equipment and standby generator shall be located outside
of the wet well in a suitable building, approved by the owner.
(2)
Automatic visual and audible alarm systems shall be provided for
all pumping stations operating independently of the station power.
The alarm shall be activated in cases of power failure, pump failure,
level control failure, or any cause of pump station malfunction. Pump
station alarms shall be telemetered, including identification of the
alarm condition to the sewage treatment plant or other location as
designated by the owner.
(3)
Ground fault interrupter (GFI) breakers shall be provided for all
dry well and exterior fixtures.
(4)
All electrical equipment and work shall comply with Fire Underwriter's
regulations for the location involved, the National Electric Code,
and OSHA 1910.147.3.C.2.
(5)
All outdoor panels and junction boxes shall be NEMA 4X 316 stainless
steel.
F.
Emergency power.
(1)
An emergency power source must be provided with automatic transfer
capability in case of primary power failure. This unit must be sized
so as to provide all power necessary to supply all the electrical
equipment for the pumping station from the period of primary power
failure.
(2)
The owner shall be supplied with 10 sets of operational instructions,
including emergency procedures and maintenance schedules. Any special
tools and spare parts as designated by the owner shall also be provided.
G.
Pumping stations - general.
(1)
Unless otherwise approved by the owner, pump stations shall be underground
concrete wet well type.
(2)
The owner shall be contacted prior to the selection of any pump and/or
pump station within the owner's service area.
(3)
Pumps and pumping stations shall be provided for transfer of raw
sewage when flow by gravity is not possible or impractical, as determined
by the owner/Engineer.
(4)
Raw sewage shall be screened before pumping unless special pumping
equipment approved by the owner is used. A trash basket and guide
rails, constructed of either aluminum or stainless steel, must be
provided in the wet well. A mechanical means, such as a winch, must
be provided so this basket can be removed from the wet well for cleaning.
(5)
Wet wells shall be provided with adequate light and ventilation and
a means of access for pumps and trash basket.
(6)
At least two pumps shall be provided at each pump station. All pumps
shall be designed for at least 2.5 times the expected average daily
flow for 10 years hence. Pumps shall be designed to overcome the total
static and ultimate dynamic head conditions of any common force main
flowing full. At the owner's discretion, variable frequency drives
(VFD) may be required for any new or rehabilitated pump station. VFD
shall be Safetronics or equal.
(b)
Three-pump system:
[1]
The pumps shall be of such capacity that with any one pump out
of service, the remaining pumps shall have the capacity to handle
the expected maximum flow.
[2]
Provisions shall also be included for all the pumps to operate
in parallel, should the level in the wet well continue to rise above
the starting level for the lead pump.
(7)
Pumps shall be capacity of passing spheres of at least three inches
in diameter, and pump suction and discharge piping shall be at least
four inches in diameter.
(8)
Pump stations shall be located outside the FEMA 100-year flood area
and shall not be subject to flooding. Pump stations shall be accessible
by motor vehicles at all times.
(9)
Pump controller.
(a)
Controller.
[1]
The PLC should be a Modicon Momentum series with the following
devices:
|
Processor
|
171CCC76010
|
|
TOD
|
Option Adapter
|
|
I/O Base 1
|
ANR 120-90
|
|
I/O Base 2
|
ADM 350-10
|
|
Com. Adapter
|
170INT 11000
|
[2]
Programming for the PLC with Concept - Version 2.6 for a complete
working duplex pump control.
[3]
Duplex pump control for VFD/bypass operation with all required
programming to accommodate items listed in HMI control paragraph.
[4]
The level control system should have a Pressure System, Incorporated's
submersible transducer, a 700 series with a 0-5V input to PLC.
[5]
Separate independent relay logic, controlled by Warrick float
balls, should be selector switch enabled to provide backup automatic
level control to the bypass starters during the event of PLC or HMI
failure. This selector switch shall disable PLC operation.
[6]
Riverside Sewerage Authority shall be provided with complete
PLC and HMI Software licenses, written programs in electronic and
paper format and PC to device cables.
[7]
The HMI interface will be a Red Lion - G308 color touch screen.
Operator programming for the G308 is free software, downloadable from
Red Lion's wet site (Crimson 2.0). Screens developed should include
the following:
[a]
Wet well level - graphical and digital readout.
[b]
Set point control.
[c]
Pump hand off auto control.
[d]
Pump hours.
[e]
Pump hours reset.
[f]
Manual speed control and time out.
[g]
Wet well pump level set point adjustment.
[j]
VFD/bypass control selection.
[k]
PID control function.
[l]
Alarm history.
(b)
Automatic pump alternation. Upon operator selection, the controller
shall select first one pump then the second pump, to run as the lead
pump for a pumping cycle. Alternation of the lag pump shall occur
similarly. All alternations shall occur at the end of a pumping cycle.
In triplex configuration, all pumps should cycle.
(c)
Transducer. The transducer shall be permanently mounted in the
wet well to accurately measure the liquid level in the wet well. The
output signal shall be proportional to the liquid level from 0% to
100%, plus or minus 1%. The sensor shall be capable of operating ranges
of one to 25 feet, and shall function over an ambient temperature
range of -40° F. to 200° F. and shall be rated FAM and CAS
for Class I and Class II hazardous environment.
(d)
Installation. The transducer shall be installed in a stilling
well constructed of three-inch diameter PVC conduit that will extend
through the top slab of the wet well. The cable outside the wet well
shall be enclosed in seal-tite conduit and supported with a unistrut
support as shown on the plan. Link seals shall be used at wet well
penetrations.
(e)
Warranty. The manufacturer of the controller shall guarantee
for one year of operation, that the equipment shall be free from defects
in design, workmanship or materials. In the event a component fails
to perform as specified or is proven to be defective in service during
the guarantee period, the manufacturer shall promptly replace the
defective part at no cost to the owner.
(10)
Provide minimum 2,000-pound capacity winch with a 2.85 to 1
cranking ratio. Winch shall be the ratchet type with a disc brake.
Winch shall be supported by a removable, swiveling-type davit. Winch
cable shall be minimum three-sixteenths-inch diameter stainless steel
and have sufficient length to reach the bottom of the wet well. The
end of the cable shall be furnished with a spring-loaded hook.
(11)
Alarm dialer.
(a)
An automatic alarm dialer shall be provided in the location
described. The alarm dialer shall be mounted and wired within the
control enclosure with the dialer's keypad and display mounted through
the enclosure door. The dialer shall be a solid state component capable
of storing and dialing up to 16 phone numbers, each up to 32 digits
in length. The dialer shall be a sixteen-channel device, wired for
the following alarm inputs:
[1]
System failure.
[2]
High water level alarm.
[3]
Generator status.
[4]
Generator failure.
[5]
Control power failure (integral to dialer).
[6]
Station temperature (integral to dialer).
[7]
Low water level alarm.
[8]
Pump No. 1 failure (high temperature, overload, pump failure).
[9]
Pump No. 2 failure (high temperature, overload, pump failure).
(b)
The dialer shall utilize digital speech recording. The dialer
shall allow the user to record and rerecord in their own voice messages
for each input channel and for the station ID. The time for each message
shall be adjustable, and recordings may be made at the front panel
or from any remote touch tone telephone. The dialer shall be Verbatim
Raco Model VSS.
(12)
Pump station design shall comply with all Occupational Safety
and Health Standards (OSHA), including Section 1910.27 for minimum
dimensions of access hatch openings.
(13)
The pump station design shall include a complete analysis of
buoyant forces. In addition, structural design calculations for all
concrete structures and metal support system shall be submitted.
(14)
Provide minimum of eight copies of all shop drawings to the
owner/Engineer prior to manufacture for review.
(15)
The pump station operation and maintenance manual shall include
at a minimum, but not be limited to, the following information:
(a)
Certified pump curves from the actual pumps being furnished.
(b)
Suggested maintenance schedule.
(c)
Complete and detailed schematics of all electrical systems and
controls, including schematic and wiring diagrams for the engine alternator
set, automatic transfer switch and interconnecting diagram showing
connections to individual components which constitute the standby
power system.
(d)
Complete and detailed exploded view drawings of all equipment
included with the pump station.
(e)
Descriptions of and operating instructions for each major component
of the pump control as supplied.
(f)
Instructions for operation of the pump controls in all intended
modes of operation.
(g)
Instructions for the adjustment, calibration, and testing of
selected electronic components or assemblies, normally considered
replaceable by the manufacturer, whose performance is not ascertainable
by visual inspection.
(16)
The owner's Engineer shall be present for on-site testing of
all equipment, including, but not limited to, determining pump capacity.
The pump station manufacturer's representative shall perform the testing.
(17)
The applicant shall coordinate progress of the work with utilities
and local authorities which require inspection and approval of the
work.
(18)
The pump station and generator manufacturers shall each provide
the services of a factory trained representative for a minimum period
of eight hours to perform initial startup of the pump station and
generator, and to instruct the owner's operating personnel in the
operation and maintenance of the equipment. This instructions time
is in addition to any required testing and equipment startup preparation.
(19)
All aluminum materials shall be suitably protected against dissimilar
materials, such as concrete, steel, nonferrous metals, etc., using
neoprene washers, painting or other approved method.
(20)
The owner shall be provided with special repair tools, spare
parts and accessories for each pump station.
(21)
In addition to the above criteria, all pump stations shall meet
the New Jersey Department of Environmental Protection Rules and Regulations
for the Preparation and Submission of Plans for Sewer Systems and
Wastewater Treatment Plants.
H.
Wet well.
(1)
Minimum wet well diameter shall be seven feet. Top of wet well slab
shall be minimum nine inches above the finished grade.
(2)
The concrete wet well construction shall conform to:
(a)
ASTM C478, Precast Reinforced Concrete Manhole Sections.
(b)
ASTM C890, Minimum Structural Design Loading for Monolithic
or Sectional Precast Concrete Water and Wastewater Structures.
(c)
ASTM C913, Precast Concrete Water and Wastewater Structures.
(d)
ASTM C443, Joints for Circular Concrete Sewer and Culvert Pipe,
Using Rubber Gaskets (for joint design only).
(e)
ASTM C923, Resilient Connectors between Reinforced Concrete
Manhole Structures and Pipes.
(3)
There shall be no joints between the base slab and first riser section,
as these two sections shall be monolithically constructed.
(4)
The floors of wet wells shall slope at least 45° toward pump
suctions to prevent solids accumulation.
(5)
Provide aluminum bar screen basket with aluminum guides, constructed
of aluminum alloy 6061-T6 or 6063-T6. All raw sewage shall be screened
before pumping unless special pumping equipment approved by the owner
is utilized. Provide removable bar screen basket with guide rails
constructed of aluminum alloy 6061-T6 or 6063-T6. Minimum 3/16 inches
by 1 1/4 inches aluminum flat bars shall be positioned on the
bottom and all sides. Maximum clear space between bars shall be one
inch. All hardware shall be stainless steel.
(6)
Provide access hatches based on the following requirements:
(a)
One access hatch shall be provided to accommodate removal of
the bar screen and for personnel access. Hatch size shall be as large
as can be structurally accommodated in the wet well top slab. Minimum
hatch width shall be 30 inches.
(b)
Each hatch shall be equipped with heavy duty hinges, lifting
handle, spring operators, automatic hold open arm with release handle,
and a snap lock with removable handle, all of stainless steel. In
addition, all hardware shall be stainless steel.
(c)
Two heavy-duty stainless steel safety chains shall be provided
on each end of all double leaf doors.
(d)
The hatch covers shall be mill finished.
(e)
All metal used in fabricating the access doors shall be either
aluminum or stainless steel. All aluminum shall be alloy 6061-T6 or
6063-T6 and all stainless steel shall be Type 316.
(f)
Each hatch shall be provided with an integral safety gate that
provides fall-through protection.
(7)
Provide an exhaust air odor control system:
(a)
Capacity minimum of 12 air changes per hour.
(b)
Unit to be Carbtrol Model G Series air purification system.
(c)
Motor shall be 115/230 VAC single phase, 3,400 rpm, with manual
starter.
(d)
Suction piping material to be PVC. Final connection to unit
shall be hose supplied with system.
(e)
PVC ball valve shall be supplied on suction side of unit for
flow control.
(f)
Provisions for manual operation only shall be provided. On/off
switch shall be located in the control room.
(g)
Applicant's engineer to specify blower capacity and static pressure,
and provide backup calculations.
(9)
All materials inside the wet well shall be aluminum alloy 6061-T6,
6063-T5 or 6063-T6, Type 316 stainless steel, PVC or fiberglass. This
includes the fall prevention system, expansion anchors, anchor bolts,
nuts and washers.
I.
Standby emergency power engine/generator.
(1)
General. The contractor shall furnish and install a complete diesel
engine/generator set, complete, at the job site. The generator set
shall be installed inside the control building. The complete standby
system shall consist of:
(a)
A diesel engine/generator set to provide standby electric power
during periods of failure of normal utility power supply. The engine/generator
capacity shall be selected on the following basis:
[1]
Engine/generator set capacity shall be sized assuming raw sewage
pumps operating with motors sized to drive pumps installed with largest
pump impeller required for all future flows and all future total dynamic
head conditions.
[2]
Starting. Unit shall be capable of simultaneously starting all
raw sewage pumps required to handle the average daily flow, and a
minimum accessory load of 6.5 KW due to auxiliary equipment and the
wet well light and blowers. Any additional loads for items such as
exterior lights shall also be included. A time delay device shall
be used to sequentially start the remaining raw sewage pumps.
[3]
Operation. Unit shall be capable of continuously running all
raw sewage pumps, the minimum 6.5 KW accessory load, exterior lights
and any other items requiring electricity to operate at the site.
[4]
Unit shall be three-phase, 60 hertz and capable of delivering
the required power as described above at 0.80 power factor.
[5]
Frequency regulation shall not exceed 3 hertz from no load to
rated load. Frequency variation shall not exceed plus or minus 0.3
hertz for constant loads from no load to rated load.
[6]
Voltage regulation from no load to rated load shall be within
plus or minus 2% of rated voltage for any size unit.
[7]
Instantaneous voltage dip for all possible sequences of load
application and motor starting for loads described in conditions of
service shall not exceed 20% of nominal voltage.
[8]
Sound attenuation: The unit shall be designed so that the maximum
sound level generated shall not exceed 90 DB at a distance of 50 feet
from the intake or the exhaust system. Sound readings shall be taken
with generator operating under a full load condition. Applicant to
provide certification from manufacturer.
(b)
Engine generator control console mounted on the generating set.
(c)
An automatic load transfer control to provide automatic starting
and stopping of the plant and switching of the load.
(d)
Mounted accessories and other equipment as specified.
(e)
Weatherproof, heavy gauge painted steel or aluminum housing
with removable side panels insulated as necessary.
(f)
A rechargeable, minimum five-pound capacity fire extinguisher
(Class ABC) mounted near the generator in a weatherproof enclosure.
(2)
Control panels:
(a)
Engine and generator control panels may be separate panels,
or a combined panel, and mounted with vibration isolators on the unit
in a NEMA 4 enclosure. Control module shall be located on the generator
end of the set. Instruments shall be of direct-reading type, factory
mounted and factory connected. Instruments shall be accurate within
3%.
(b)
Provide engine panel with following minimum features and instruments:
[1]
Three-position run-stop-remote switch.
[2]
Manual starting switch.
[3]
Full automatic starting from pilot device initiating start when
normal power fails. Automatic cranking shall be interrupted cycle
type not affected by ambient temperature with overall time limit.
A total of three cranking cycles (approximately 10 seconds each) shall
automatically shut down engine.
[5]
Indicator lamps shall be provided to signal the following functions:
[a]
Run. Indicates start disconnect.
[b]
Overcrank. Indicates the starter has been locked
out because cranking time was excessive.
[c]
Overspeed. Indicates engine has shut down because
of excessive rev/min.
[d]
High engine temperature. Indicates engine has shut
down because of critically high temperature.
[e]
Low oil pressure. Indicates engine has shut down
because of critically low oil pressure.
[f]
Pre-high engine temperature. Indicates engine temperature
is marginally high.
[g]
Pre-low oil pressure. Indicates oil pressure is
marginally low.
[h]
Low engine temperature. Indicate engine temperature
is marginally low for starting.
[i]
Switch off (flashing). Indicates control switch
is in the stop position.
[j]
Low fuel. Indicated fuel supply is marginally low.
[k]
Two spare faults (red), for future owner use.
[6]
A fault reset switch shall be provided to clear fault indications
and allow restarting of the engine after shutdown faults. The control
design shall be such that the fault indication shall remain until
reset. The fault indicator memory shall not be dependent on the presence
of either AC or DC voltage and shall retain the fault status memory
even through complete removal and replacement of the starting batteries.
The fault reset function shall operate only when the run-stop remote
switch is in the stop position.
[7]
A locking screwdriver type potentiometer shall be provided to
adjust the voltage ±5% from rated value.
[8]
Manual reset exciter field circuit breaker.
[9]
AC voltmeter, 90° scale, 2 1/2 inches (61.25mm) flange,
2% switchboard meter.
[10]
AC ammeter, 90° scale, 2 1/2 inches (61.25mm) flange,
2% switchboard meter.
[11]
Frequency meter 45-65 Hz., 90° scale, 1 1/2 inches
(61.25mm) flange ±0.6 Hz panel meter.
[12]
Four -position Ac meters phase selector switch to read line
current and voltage in each phase with off position.
[13]
Water temperature gauge.
[14]
Ammeter charging circuit.
[15]
Lubricating oil pressure gauge.
[16]
Running time meter.
[17]
Light with on/off switch for panel illumination.
(3)
Appurtenances. All accessories needed for the proper operation of
the pump station and generator shall be furnished. These shall include,
but be limited to, the following:
(a)
A painted critical-type exhaust muffler, and stainless steel
flexible exhaust connection. Muffler shall be factory mounted on the
housing with the condensate drain located at the bottom. To prevent
birds from entering the muffler, a threaded exhaust piping extension
shall be installed with the end of the piping cut at a 45 angle. The
shortest end of the pipe shall be on the bottom.
(b)
Aboveground fuel tank shall be the double-walled skid-type,
mounted directly below the generator. Tank capacity shall be either
75 gallons or sufficient capacity to operate the generator at full
load for 12 consecutive hours, whichever is greater. Aboveground storage
tanks shall not exceed 660 gallons unless they conform to NFPA 30
and the Uniform Construction Code. Fuel system shall include fuel
gauge, fuel lift pump (if recommended by generator manufacturer),
and all necessary fuel piping. Fuel piping shall be Type K soft temper
copper tubing, or as recommended, and installed by the manufacturer.
All aboveground fuel storage tanks shall be designed and installed
in conformance with NJDEP requirements.
(c)
A mechanical governor capable of maintaining engine speed within
5% of synchronous speed from no load to full load shall be furnished.
(d)
Control wires running between generator and transfer switch
shall have termination identification on both ends. Identification
shall be provided for each device or function and shall be silk-screened
white on a black background.
(4)
Paint:
(a)
Unless otherwise noted, paint for exterior surfaces of equipment
(including skids) shall be two coats of acceptable oil and heat-resistant
paint, applied after surfaces have been thoroughly cleaned and prepared
with suitable priming coat. Color for weatherproof housing and automatic
transfer switch shall be green, unless otherwise approved.
(b)
The generator muffler shall be protected with two coats of high
heat aluminum paint. The paint system shall be primed in accordance
with the manufacturer's recommendations.
(c)
All painted surfaces damaged during installation shall be restored
by the applicant/developer.
(6)
Automatic load transfer control:
(a)
The complete automatic load transfer control shall include the
necessary relays and components parts, together with UL-listed and
tested interlocked contactor, and shall provide the following functions:
[1]
Upon normal power line outage, automatically start the pump
station, and when the pump station comes up to voltage, disconnect
the normal circuits from the main line and transfer them to the emergency
pump station's output.
[2]
Upon power line return, transfer the load back to the line and
stop the pump station.
(b)
Each contact pole of the main transfer device shall be double-break
design, with solid silver cadmium contacts, capable of handling both
noninductive and inductive loads and allow for inrush currents of
20 times the continuous rating. Contact pressure shall be maintained
by a coil spring, not a part of the current-carrying path. The ampere
rating of the transfer switch shall be sufficient to handle the capacity
of the pump station and loads being transferred.
(c)
The control shall contain either a twelve-volt or twenty-four-volt,
fused, battery trickle charging circuit, with a rheostat and ammeter,
to maintain starting batteries fully charged.
(d)
The automatic transfer switch shall be provided with terminal
lugs for copper wire and shall have individual, heat resistant chambers
to protect against arcing. The transfer switch shall be provided with
mechanical and electrical interlocks to prevent simultaneously energizing
both normal and emergency service.
(e)
The transfer switch shall be located in a NEMA 1 enclosure which
is contained in a separate NEMA 4 enclosure, if skid mounted for outdoor
use.
(f)
Control accessories in the NEMA 1 enclosure shall mount on a
dead front, swing out control accessory panel to avoid shock hazard
while adjusting control functions, but will swing out exposing the
wiring to facilitate servicing. Indicating lamps and meters shall
be set in a front mounted panel to be visible with only opening the
NEMA 4 enclosure door.
(g)
Solid-state voltage sensors shall simultaneously monitor all
phases of the normal source and all phases of the emergency source
to provide adjustable range sensors for field adjustment for specific
application needs. Voltage sensors shall be temperature compensated
type, for maximum deviation over the temperature range of -20°
F. to +175° F. Voltage sensors shall allow for adjustment to sense
partial loss of voltage on any phase or normal or emergency source,
even where motor feedback voltages exist.
(h)
Controls shall signal the emergency power system to start upon
signal from normal source voltage sensors. Solid-state time-delay
start, adjustable from zero seconds to five seconds, shall avoid nuisance
startups on momentary voltage dips or momentary interruptions.
(i)
Switch shall transfer the load to the emergency power system
after the generator set reaches proper voltage and frequency. Solid-state
timer-delay transfer, adjustable from two seconds to 120 seconds,
shall allow the engine-generator set to stabilize before application
of load.
(j)
The transfer switch shall control the generator set to allow
generator set to start and transfer load within 10 seconds after normal
source power failure.
(k)
Switch shall retransfer the load to the normal source after
normal power restoration. Solid-state time-delay retransfer, adjustable
from zero minutes to 30 minutes, shall allow:
(l)
The operating power for transfer and retransfer shall be obtained
from the source to which the load is being transferred. Controls shall
provide an automatic retransfer of the load from emergency source
to normal source if emergency source fails when normal source is available.
(m)
Transfer switches shall have the "programmed transition" feature
available by plugging the proper program timer into the factory installed
timing receptacle. This provides the capability of either factory
or field installation of this feature. This feature shall incorporate
a field adjustable time delay of 1.5 seconds to 15 seconds. The time
delay shall occur during switching in both directions, during which
time the load is isolated from both normal and emergency sources.
This will allow residual voltage components of motors or other inductive
loads (such as transformers) to decay before completing the switching
cycle. The program timer shall be connected in a manner that will
not cause the time delay in switching, where the time delay as already
been established by the loss of voltage to the load during normal
source power interruptions. Transfer methods that use the phase relationships
between the two power sources to control initiation time are not acceptable.
Provide program timer.
(n)
Status indicators.
[1]
Controls shall provide built-in "control mode status indicators",
consisting of LEDs to indicate a sequence of functions, such as the
following:
[2]
These indicators shall allow the operator to determine that
the controls are properly sequencing and shall assist in determining
sequence of any malfunctions that might occur.
(o)
Provide position indicator lamps (green "NORMAL" and red "EMERGENCY")
and a key operated selector switch to provide the following positions
and functions:
[1]
Test. Simulated normal power loss to control unit for testing
of generator set, including transfer to load. Control system shall
provide for "system test without load transfer" for use in that manner
when desired.
[2]
Normal. This is normal operating position and it restores the
load to the normal source after test and after time delays.
[3]
Retransfer. Momentary position to override retransfer time delay
and cause immediate return to normal source after test or actual outage.
(p)
Provide exerciser clock to set the day, time and duration of
generator set period; also include "with/without load" selector switch.
Clock shall have a one-week dial minimum. If normal power is interrupted
while the generator is exercising at no load, the load is immediately
transferred to the set.
(q)
Provide battery charger, SCR voltage regulated type, with float
and taper features; 12 or 24 VDC as required for generator set. Charger
shall have charging ammeter and fuse protection. Charger shall not
be damaged during engine cranking.
(r)
Transfer switch capacity shall be no smaller than the disconnect
switch capacity.
(s)
Provide contacts to operate an alarm light in the dry well and
a remote alarm indicating the generator is supplying power to the
dry well. Upon automatic shutdown, the signal will be deactivated.
(7)
Products:
(a)
Single manufacturer. This equipment shall be manufactured by
a single-source manufacturer who has been regularly engaged in the
production of engine-generator sets. The emergency electric generating
system described herein, including these components, shall be factory
built, factory tested, and shipped by one source of supply and responsibility
for warranty, parts and service. This manufacturer shall have a local
representative who can provide factory-trained servicemen, required
stock of replacement parts, and technical assistance.
(b)
Safety standards. The electric generating system must meet all
requirements of NFPA 110 (latest edition) including design specifications,
prototype tests, one-step full-load pickup, and installation acceptance.
Automatic transfer switch shall conform to UL 1008.
(c)
The responsibility for performance to this specification includes
the entire system and cannot be split up among individual suppliers
of components comprising the system, but must be assumed solely by
the supplier of the system.
(d)
All controls shall be the standard of the manufacturer, who
is engaged in the manufacture of engine-generator sets, transfer switches,
and accessories and has then available for sale on the open market.
Control parts shall be identified by part numbers of this manufacturer
and shall have second source listing where applicable.
(8)
Field quality control. Provide full load test utilizing portable
test bank for four hours minimum. Simulate power failure including
operator of transfer switch, automatic starting cycle, automatic shutdown
and return to normal. All testing procedures shall be as described
in NFPA 110 under Installation Acceptance.
(9)
Personnel training. The generator manufacturer shall provide the
services of a factory-trained representative for a minimum period
of eight hours to perform initial startup of the generator, and to
instruct the owner's personnel in the operation and maintenance of
the equipment. Initial startup of generator shall conform to NFPA
110.
(10)
Shop drawings and O&M manuals:
(a)
Applicant's engineer to specify generator capacity and shall
provide owner with backup information justifying the capacity selection.
As a minimum, backup information shall identify motor horsepower and
accessory load, motor voltage, motor code letter, starting sequence,
and full or reduced voltage starting requirements. Manufacturer's
load calculation sheets for both the specified generator and the furnished
generator shall be submitted to the owner.
(b)
Applicant shall provide eight copies of manufacturer's shop
drawings for approval prior to fabrication. All eight copies will
be utilized by the owner and the applicant shall furnish additional
copies for his use. As a minimum shop drawings shall contain:
[1]
Plan and elevation views with both overall and interconnection
point dimensions, fuel consumption rate curves at various loads, ventilation
and combustion air requirements, and electrical diagrams including
schematic and interconnection diagrams.
[2]
Product data showing dimensions, weights, ratings, interconnection
points, and internal wiring diagrams for engine, generator, control
panel, transfer switch, battery, battery rack, battery charger, exhaust
silencer, vibration isolators and skid tank.
[3]
Warranty data.
[4]
Generator capacity with backup information justifying the capacity
selection. As a minimum, backup information shall identify motor horsepower
and accessory load, motor voltage, motor code letter, starting sequence,
and full or reduced voltage starting requirements. Manufacturer's
load calculation sheets for the furnished generator shall be submitted
for approval.
(c)
Provide 10 copies of the generator operations and maintenance
manual, including, but not limited to:
[1]
As-built plans of the concrete support pad and conduit locations.
[2]
Suggested maintenance schedule and step-by-step maintenance
procedures.
[3]
Complete and detailed schematics of all electrical system and
controls, including schematic and wiring diagrams for the engine alternator
set, automatic transfer switch and an interconnecting diagram showing
connections to individual components which constitute the standby
power system.
[4]
Complete and detailed exploded view drawings of all equipment.
Include descriptions of all parts.
[5]
Copy of all approved shop drawings.
(d)
All operation and maintenance and warranty materials shall be
submitted before testing of the generator takes place.
(11)
Warranty. The complete standby electric power system, including
engine-generator set and transfer switch equipped with set exerciser,
and running time meter, shall be warranted for a period of five years
or 1,500 operating hours, whichever occurs first, from the date of
initial startup. During the warranty period, manufacturer shall promptly
furnish the owner with replacement parts for all items deemed defective.
Multiple warranties for individual components (engine, generator,
controls, etc.) will not be acceptable. Satisfactory warranty documents
must be provided. This warranty shall be detailed in available written
documents. In the judgment of the owner, the manufacturer supplying
the warranty for the complete system must have necessary financial
strength and technical expertise with all components supplied to provide
adequate warranty support.
J.
Pump station site.
(1)
Provide minimum seven-foot-high fence along the pump station area
perimeter. All fence shall be located a minimum of 10 feet behind
the present or future public right-of-way line or privately owned
curbing and sidewalk. All slabs, equipment and utilities shall be
located within the fenced area at least three feet from the fence.
(2)
Adequate light and ventilation shall be provided at all pumping stations.
Where operation or maintenance duties are required in enclosed areas
or pits, forced ventilation by suitable means shall be provided with
sufficient capacity to induce at least 30 air changes per hour. Explosion-proof
equipment shall be utilized.
(3)
Adequate fresh water facilities shall be provided to permit routine
washdown and cleaning operations at all pumping stations. Where a
domestic service connection is provided to a pumping station, the
water supply shall be properly protected with an appropriate backflow
prevention device. No cross-connections between fresh water and sewage
pumps or pipes shall be permitted.
(4)
Sewage pumping station structures and electrical and mechanical equipment
shall be protected from physical damage by the 100-year flood. Sewage
pumping stations shall remain fully operational and accessible during
the twenty-five-year flood.
(5)
The pumping station shall be readily accessible by maintenance vehicles
during all weather conditions.
(6)
A paved access road shall be provided for ingress and egress to the
pump station. The access drive shall include a turnaround area.
(7)
The entire site shall be fenced, and all appurtenances located within
minimum 50 feet by 50 feet parcel.
(8)
Site area lighting shall be provided and shall be shielded as necessary
to protect adjacent uses from nuisance lighting.
(9)
Sheared white pine screening, or approved substitution, shall be
provided around the outside perimeter of the station fence. Provide
an eight-foot-wide stone mulch area (six inches thick) with polyethylene
wood barrier below starting out from the edge of the pump station
pavement.
(10)
Provide a source of potable water with a frostproof post hydrant
and one inch hose bib connection.
(11)
Within the pump station fenced-in area, provide a Woodford Iowa
Model Y1 or approved equal freeze-proof post hydrant with one-inch
inlet, three-quarter-inch threaded brass hose nozzle, three-quarter-inch
galvanized steel pipe outer casing, one-eight-inch drain hole and
furnished for four-foot depth of bury. Provide Nidel Model 34HD vacuum
breaker-backflow preventer. Provide minimum one cubic yard of three-quarter-inch
washed gravel below hydrant for drainage purposes.
(12)
Provide 50 feet of three-quarter-inch heavy-duty, double layer
nylon reinforced rubber water hose. Provide a high-pressure adjustable
brass nozzle with adjustable spray pattern and removable barrel to
fit the hose. Provide a galvanized steel hose rack on a stand located
adjacent to the post hydrant. Stand shall be three feet high by two-inch
diameter Schedule 40 stainless steel pipe with pipe cap. Set pipe
two feet deep with twelve-inch diameter by two feet deep concrete
footing. Bolt rack to pipe with 2-1/4-20 by three-inch stainless steel
carriage bolts with self-locking nuts. Post hydrant, hose rack and
stand shall all be painted green. Hydrant and stand to be located
out of the motor vehicle traffic area. No connections between fresh
water and sewage pumps or pipes shall be permitted.
(13)
Pavement to extend six inches beyond fence perimeter. Apply
tack coat conforming to NJDOT Standard Specifications Grade RC-70
or RC-T cutback asphalt or Grade SS-1 emulsified asphalt, Section
904.02 or 904.03, over entire stabilized base course.
(14)
Extending from the wet well area pavement shall have minimum
0.75% slope towards fence. Finished surfaces shall be free from all
roller marks, ridges and voids. Surfaces will not be acceptable if
any puddling is possible or if slope is off more than 1/4 inch in
10 feet when tested in any direction.
(15)
Provide a fifteen-foot-wide driveway up to the pump station
gate. Cantilevered slide gate shall be minimum 12 feet wide. A motor
vehicle entering the site shall have the ability to drive to both
the wet well and dry well. The access drive shall include a turnaround
area.
(16)
All bolts, nuts, and washers whether buried, embedded in concrete
or exposed above grade shall be stainless steel. All nuts and rods
for harnessing shall be bituminous coated.
(17)
The pump station property line shall extend to at least 10 feet
outside the pump station fence and shall include the access road and
turnaround area.
(18)
Pump station shall include a bypass pumping valve pit. Valve
pit shall be constructed per Township of Riverside standard detail.
(19)
Sump pump piping sleeves and wet well joint leakage test. Before
putting the pump station into operation, the contractor shall fill
the wet well to the top with clean water to demonstrate both the sleeves
connecting the wet well and dry well and all the wet well joints are
watertight. Water level shall be maintained at top of the wet well
slab for one hour by the contractor without the addition of water.
Before the test commences, the contractor shall position a sufficient
number of pumps to dewater the dry well in the event of a leak. If
the test is unsuccessful, the contractor shall make repairs and retest
sleeves as many times as is necessary.
(20)
All tests shall be conducted in the presence of the Engineer.
(21)
All pumping station sites must be provided with a street address
on a separate parcel with a distinct lot and block number.
B.
Materials. Furnish pumps, valves, plugs, taps, pressure gauges, air
compressor, and all other equipment required for testing of piping
system.
C.
Method of testing: exfiltration test for gravity sanitary sewer lines.
(1)
General requirements:
(a)
Perform all tests in presence of the Engineer.
(b)
Conduct exfiltration test when all utilities (including gas,
water, telephone, sewers), manholes, and laterals have been installed.
(c)
Establish test sections between consecutive manholes as directed
by the Engineer.
(d)
All requirements of this specification shall be met prior to
acceptance of sewer facilities by the Engineer.
(2)
Procedure for exfiltration test (low pressure air test, 3.5 lbs.):
(a)
Plug test section of sewer line at each end. Tap one plug and
provide air inlet connection for filling pipe from air compressor.
(b)
Cap or plug all service laterals, stubs and fittings connecting
to sewer test section, brace same against internal pressure to prevent
air leakage by slippage and blowouts.
(c)
Connect air hose to tapped plug selected for air inlet. Connect
other end of air hose to portable air control equipment used for controlling
air entry rate to sewer test section and monitoring air pressure in
pipeline.
(d)
Air control equipment shall include shutoff valve, pressure
regulating valve, pressure reduction valve and monitoring pressure
gauge having pressure range from zero psi to five psi and an accuracy
of +0.04 psi.
(e)
Connect another air hose between air compressor (or other source
of compressed air) and air control equipment. This completes test
equipment set up.
(f)
Supply air to test section slowly, filling pipeline until constant
pressure of 3.5 psig is maintained. Air pressure must be regulated
to prevent pressure inside the pipe from exceeding 5.0 psig.
(g)
When constant pressure of 3.5 psig is reached, throttle air
supply to maintain internal pressure above 3.0 psig for at least five
minutes, permitting temperature of entering air to equalize with temperature
of pipe wall. During this stabilization period, check all capped and
plugged fittings with a soap solution to detect leakage at connections.
(h)
If leakage is detected, release pressure in line and tighten
all leaky caps and plugs. Start test operation again by supplying
air. When necessary to bleed off air to tighten or repair faulty connection,
a new five-minute interval shall be allowed after pipeline has been
refilled.
(i)
After stabilization period, adjust air pressure to 3.5 psig
and shut off or disconnect air supply. Observe gauge until air pressure
reaches 3.0 psig. At 3.0 psig commence timing with a stopwatch that
is allowed to run until the line pressure drops to 2.5 psig. The time
required, as shown on the stopwatch, for a pressure loss of 0.5 psig
is used to compute air loss.
(j)
If the time, in minutes and seconds, for the air pressure to
drop from 3.0 to 2.5 psig is greater than that shown in Table 1 for
designated pipe size, the section undergoing test shall have passed.
(k)
If the time, in minutes and seconds, for 0.5 psig drop is less
than shown in Table 1 for designated pipe size, the section of pipe
shall have failed the test. Necessary repairs shall be made by the
contractor and the line retested.
|
*Table 1
Time Requirements for Air Testing For Sewer Line of Uniform
Pipe Size
| ||
|---|---|---|
|
Pipe Size
(inches)
|
Time
| |
|
Minutes
|
Seconds
| |
|
**4
|
2
|
32
|
|
**6
|
3
|
50
|
|
**8
|
5
|
6
|
|
10
|
6
|
22
|
|
12
|
7
|
39
|
|
14
|
8
|
56
|
|
15
|
9
|
35
|
|
16
|
10
|
12
|
|
18
|
11
|
34
|
|
20
|
12
|
45
|
|
21
|
13
|
30
|
|
NOTES:
| |
|---|---|
|
*
|
Multi-pipe sizes: When sewer line undergoing test is eight-inch
or larger diameter pipe and includes different sized laterals, the
figure in Table 1 for uniform sewer main sizes will not give reliable
or accurate criteria for the test. Where multi-pipe sizes are to undergo
air testing, the Engineer will compute "average" size in inches which
is multiplied by 38.2 seconds. The results give minimum time in seconds
acceptable for pressure drop of 0.5 psig for "average" diameter pipe.
|
|
**
|
For eight-inch and smaller pipe only, if during the five-minute
stabilization period pressure drops less than 0.5 psig after initial
pressurization and air is not added, pipe section undergoing test
shall have passed.
|
(3)
Procedure for air pressure correction due to groundwater:
(a)
Air pressure correction is required when prevailing groundwater
is above sewer line being tested. Under this condition, air test pressure
shall be increased 0.433 psi for each foot groundwater level is above
invert of pipe.
(b)
Establish height of groundwater (in feet) above pipe invert:
[1]
During sewer and manhole construction, install one-half-inch
diameter pipe nipple (threaded one or both ends, approximately 10
inches long) through manhole wall directly on top of one of sewer
pipes entering manhole, with threaded end of nipple extending inside
the manhole.
[2]
Seal pipe nipple with a threaded one-half-inch cap.
[3]
Immediately before air testing, determine groundwater level
by removing the threaded cap from nipple, blowing air through the
pipe nipple to remove any obstructions, and connecting clear plastic
tube to pipe nipple.
[4]
Hold plastic tube vertically permitting water to rise to groundwater
level.
[5]
After water level has stabilized in plastic tube, measure vertical
height of water, in feet, above invert of sewer pipe.
(c)
Determine air pressure correction, which is added to 3.0 psig
normal starting pressure of test, by dividing the vertical height
in feet by 2.31. The result gives air pressure correction in pounds
per square inch to be added:
[1]
Example: If the vertical height of water from the sewer invert
to the top of the water column measures 11.55 feet, the additional
air pressure required would be:
|
(11.55)
|
=
|
5 psig
|
|
2.31
|
[2]
Starting pressure of the test would be 3.0 plus 5 or 8.0 psig,
and the one-half-pound drop becomes 7.5 psig. There is not change
in the allowable drop (0.5 psig) or in the time requirements established
for the basic air test.
D.
Methods of testing: infiltration test.
(2)
Procedure for infiltration test:
(a)
Examine the sanitary sewer system for infiltration at the downstream
end of the system after construction has been completed.
(b)
In the event that there is infiltration and water is flowing
at the downstream end of the system, then the source and volume of
flow shall be determined by an infiltration test.
(c)
The test shall consist of isolating the source of infiltration
by plugging the first upstream manhole and observing to see if the
flow stops. This procedure is repeated one manhole at a time until
each source has been isolated.
(d)
When the infiltration has been isolated to a section or area,
the volume of flow shall be determined using a 90° V-notch weir
inserted into the pipe.
(e)
The actual infiltration rate will be determined by the Engineer
based on the weir measurements. This rate will be compared with the
allowable infiltration rate of 50 gallons/inch diameter/mile of pipe/per
day (24 hours).
(f)
If the allowable infiltration rate is greater than the actual
infiltration rate, the infiltration test passes. If the actual infiltration
is greater than the allowable infiltration, the infiltration test
fails.
(g)
In the event the infiltration test fails, the section of the
pipe involved shall be repaired as necessary and the test repeated.
A.
Description. Test sanitary sewer gravity and force mains for exfiltration.
B.
Materials. Furnish pumps, valves, taps, pressure gauges, meter, and
all other equipment required for testing of piping systems.
C.
Method of testing: exfiltration test.
(1)
General requirements:
(2)
Procedure for exfiltration test:
(a)
Expel air from pipe through blowoffs, or taps required for release
of air from high points. Taps for release of air and blowoffs for
filling pipe and releasing air shall be provided by the contractor.
(b)
Fill each pipe section slowly with water, and subject pipe to
hydrostatic pressure of 150 psi for one hour.
(c)
When test pressure is reached, measure amount of make-up water
required to maintain this pressure during the one-hour test period.
(d)
Leakage shall not exceed 12 gallons per inch of diameter per
mile of pipe per day. Pipelines failing to meet this requirement shall
be repaired and retested as above specified.
(e)
Compute leakage as follows:
