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3.03 BACKFILL PLACEMENT AND COMPACTION:

A. GENERAL:

1.

2.

Prior to backfilling, the Contractor shall compact the exposed natural sub-
grade to the densities as specified herein.
After approval of sub-grade by the Engineer, the Contractor shall backfill areas
to required contours and elevations with specified materials.
The Contractor shall place and compact materials to the specified density in
continuous horizontal layers. The degree of compaction shall be based on
maximum dry density as determined by ASTM Test D 1557, Method C. The
minimum degree of compaction for fill placed shall be as follows:
Percent of

Location Maximum Density
Below pipe centerline 95
Above pipe centerline 92
Below pavement (upper 3 ft.) 95
Embankments 95
Below pipe in embankments 95
Adjacent to structures 92
Below structures 95
The Engineer reserves the right to test backfill for conformance to the
specifications and Contractor shall assist as required to obtain the information.
Compaction testing will be performed by the Engineer or by an inspection
laboratory designated by the Engineer, engaged and paid for by the Contractor.
If test results indicate work does not conform to specification requirements, the
Contractor shall remove or correct the defective Work by re-compacting where
appropriate or replacing as necessary and approved by the Engineer, to bring
the work into compliance, at no additional cost to the Owner. All backfilled
materials under structures and buildings shall be field tested for compliance
with the requirements of this specification.
Where horizontal layers meet a rising slope, the Contractor shall key each layer
by benching into the slope.
If the material removed from the excavation is suitable for backfill with the
exception that it contains stones larger than permitted, the Contractor has the
option to remove the oversized stones and use the material for backfill or to
provide replacement backfill at no additional cost to the Owner.
The Contractor shall remove loam and topsoil, loose vegetation, stumps, large
roots, etc., from areas upon which embankments will be built or areas where
material will be placed for grading. The sub-grade shall be shaped as indicated
on the Drawings and shall be prepared by forking, furrowing, or plowing so
that the first layer of the fill material placed on the sub-grade will be well
bonded to the sub-grade.

2019 Sewer Replacement Project Earthwork

Nashua, NH

02300-6

B. TRENCHES:

1.

we

Bedding as detailed and specified shall be furnished and installed beneath the
pipeline prior to placement of the pipeline. A minimum bedding thickness shall
be maintained between the pipe and undisturbed material, as shown on the
Drawings.

As soon as practicable after pipes have been laid, backfilling shall be started.
Unless otherwise indicated on the Drawings, select backfill shall be placed by
hand shovel in 6-inch thick lifts up to a minimum level of 12-inches above the
top of pipe. This area of backfill is considered the zone around the pipe and
shall be thoroughly compacted before the remainder of the trench is backfilled.
Compaction of each lift in the zone around the pipe shall be done by use of
power-driven tampers weighing at least 20 pounds or by vibratory compactors.
Care shall be taken that material close to the bank, as well as in all other
portions of the trench, is thoroughly compacted to densities required.

Trench backfill shall be placed from the top of the select backfill to the
specified material at grade (loam, pavement sub-base, etc.). Fill compaction
shall meet the density requirements of this specification.

Water Jetting:

a. Water jetting may be used when the backfill material contains less than
10 percent passing the number 200 sieve, but shall be used only if
approved by the Engineer.

b. Contractor shall submit a detailed plan describing the procedures he
intends to use for water jetting to the Engineer for approval prior to any
water jetting taking place.

c. Compaction of backfill placed by water jetting shall conform to the
requirements of this specification.

If the materials above the trench bottom are unsuitable for backfill, the

Contractor shall furnish and place backfill materials meeting the requirements

for trench backfill, as shown on the drawings or specified herein.

Should the Engineer order crushed stone for utility supports or for other

purposes, the Contractor shall furnish and install the crushed stone as directed

by the Engineer.

In roadways, the specified base course gravels and pavement shall be placed as

specified.

A tracer tape shall be furnished and installed as specified Section 02518,

TRACER TAPE

C. BACKFILLING ADJACENT TO STRUCTURES:

1. The Contractor shall not place backfill against or on structures until they have
attained sufficient strength to support the loads to which they will be
subjected. Excavated material approved by the Engineer may be used in
backfilling around structures. Backfill material shall be thoroughly compacted
to meet the requirements of this specification.

2019 Sewer Replacement Project Earthwork
Nashua, NH 02300-7

2. Contractor shall use extra care when compacting adjacent to pipes and
drainage structures. Backfill and compaction shali proceed along sides of
drainage structures so that the difference in top of fill level on any side of the
structure shall not exceed two feet (2') at any stage of construction.

3. | Where backfill is to be placed on only one side of a structural wall, only hand-
operated roller or plate compactors shall be used within a lateral distance of
five feet (5') of the wall for walls less than fifteen feet (15') high and within ten
feet (10') of the wall for walls more than fifteen feet (15") high.

3.04 DISPOSAL OF SURPLUS MATERIALS:

A. No excavated material shall be removed from the site of the work or disposed of by
the Contractor unless approved by the Engineer.

B. Surplus excavated materials, which are acceptable to the Engineer, shall be used to
backfill normal excavations in rock or to replace other materials unacceptable for
use as backfill.

C. Surplus excavated clean material not needed as specified above shall be hauled away
and disposed of by the Contractor at the Nashua Landfill. Arrangements must be
made with the landfill prior to delivery. Disposal of all rubble shall be in
accordance with all applicable local, state and federal regulations.

END OF SECTION

2019 Sewer Replacement Project Earthwork
Nashua, NH 02300-8

SECTION 02370
EROSION CONTROL
PART 1 - GENERAL

1.01 WORK INCLUDED:
A. Provide temporary erosion control for the entire duration of project in accordance with

plans, specifications.
B.
1.02 RELATED WORK:
A. Section 02300: EARTHWORK
B. Section 02745: ROAD RESTORATION
C. Section 02920: LOAMING AND SEEDING

1.03 SITE CONDITION:

A. All soil erosion and sediment control measures to be in accordance with standards and
specifications thereof in "Stormwater Management, and Erosion and Sediment Control
Handbook for Urban and Developing Areas in New Hampshire," April 1997, prepared
by Rockingham County Conservation District for NHDES in cooperation with USDA-
SCS.

B. The work area shall be graded, shaped, and otherwise drained in such a manner as to
minimize soil erosion, siltation of drainage channels, damage to existing vegetation,
and damage to property outside the limits of the work area. Silt fences, hay bales
and/or detention basins will be necessary to accomplish this end.

PART 2 —- PRODUCTS
2.01 MATERIALS:

A. SILTSACK®:

Sediment control devices at catch basins shall be SILTSACK® as manufactured by
Terrafix Geosynthetics, Inc., or approved equal.

B. Stabilized Construction Entrance:

2019 Sewer Replacement Project Erosion Control
Nashua, NH 02300-1

Stabilized construction entrance shall conform to the plans and requirements of the
“Erosion and Sediment Control Design Handbook for Developing Areas of New
Hampshire.”

PART 3 —- EXECUTION
3.01 SILTSACKs® AND STABILIZED CONSTRUCTION ENTRANCE:

A. All SILTSACKs® shall be installed in accordance in all catch basins that receive flow
from the disturbed area of the project.with the manufacturer’s recommendations.

B. SILTSACKs® shall not be removed until finish grading, paving and final loam and
seeding have been completed. Maintain SILTSACKs® in good conditions until
removed.

3.06 ROADWAYS AND PAVEMENT AREAS:
A. As soon as possible after utility work has been installed, the roadways shall be brought

to subgrade, and temporary or permanent gravel base and pavement shall be placed.as
per Specifications.

3.07 REMOVAL OF TEMPORARY EROSION CONTROL MEASURES:
A. All temporary erosion control measures shall be removed once the site has been

stabilized with final pavement, and disturbed loam and seed areas have established a
viable stand of grass.

END OF SECTION

2019 Sewer Replacement Project Erosion Control
Nashua, NH 02300-2

SECTION 02441

CLEANING AND TELEVISION INSPECTION OF PIPELINES

PART 1 - GENERAL
1.01 WORK INCLUDED:

A. The Contractor shall furnish all materials, tools, labor and equipment necessary to clean the
pipeline of debris, and visually inspect by means of a closed-circuit television (CCTV) of
sewers as requested by the Engineer as hereinafter specified.

102 RELATED WORK:

A. Section 01330, SUBMITTALS

B. Section 01331, DOCUMENTATION
103 QUALITY ASSURANCE:

A. The work described herein shall be performed by a company with not less than five (5) years
of experience in providing the required services, employing experienced workers and
experienced supervisory personnel. Supervisory personnel shall have not less than three
years of experience in providing the required services and shall be present at the jobsite

during all work related to the required services.

1.04 SUBMITTALS: IN ACCORDANCE WITH REQUIREMENTS OF GENERAL
SPECIFICATIONS, SUBMIT THE FOLLOWING:

A. Prior to beginning work, submit six (6) sets of the following:
1. Qualifications of the firm/personnel who will perform the work;

2. Description of system proposed for handling existing flows during the various
procedures to be carried out;

3. Description of the system and equipment proposed for cleaning;
4. Description of the system and equipment proposed for root cutting; and

5. Description of the system and equipment proposed for televising the pipe after
cleaning.

2019 Sewer Replacement Project Cleaning and Television Inspection of Pipelines
Nashua, NH 02441-1

The H.L. Turner Group Inc.

27 Locka Road Concord, NH 03301

: 603.228.1122 hiturner.com

Nashua Riverfront Development Project
Final Engineering Design

5/11/2022
TASK DESCRIPTION WORK HOURS TOTAL
PM Structural PE Sr PD re HOURS
Segment 3 - Substation Screening
3.1 - Metal Screening Structure 4 24 ed 40 2 70
3.2 - Foundation Design 8 8
Preliminary (completed) 8 36 2 46
Final Design 8 24 2 34
3.3 - Flood Resillency Evaluation 8 74 2 34
i
oll tee Nee Ae hee Re dee Re TT ie
36 84 24 40 8 192
fs ca nes nes sy ETO SED SEED SP ND GND GD Gems mi mth ms ms sys xp Gu cae cme cre cme cm fms cm we oom fen om am cm if nme mess cs os cf ce oe
TOTAL HOURS 36 84 24 40 8 192
ESTIMATED ENGINEERING COSTS
Work Estimated
Hours Hourly Rate Costs
Project Manager (PM) 36 5 150.00 § 5,400.00
Structural Engineer (Structural) 84 § 185.00 § 15,540.00
Project Engineer (PE} 24 $ 130.00 $ 3,120.00
Sr. Project Designer } (Sr PD) 40 $ 105.00 $ 4,200.00
Technical Coordinator {TC) 8 $ 100.00 $ 800.00
192 Total Fully Burdened Labor $ 29,060.00
Geotech Subconsultant $ -
Expenses $ 150.00
Estimated Direct Costs $ 150.00
TOTAL ESTIMATED COST= $ 29,210.00

PART2-PRODUCTS

2.01

A.

B.

EQUIPMENT:
DVD (Read only) video system shall be used which utilizes standard DVD recording discs.

The television camera used for the inspection shall be a pan and tilt closed circuit color
television camera specifically designed and constructed for such inspections. Lighting for
the camera shall be suitable to allow a clear picture for the entire periphery of the pipe.
The camera shall be operative in 100 percent humidity conditions. The camera, television
monitor and other components of the video system shall be capable of producing a
minimum 400 line resolution color video picture. Picture quality and definition shall be to the
satisfaction of the Engineer and, if unsatisfactory, equipment shall be removed and no
payment made for the unsatisfactory inspection.

PART 3-EXECUTION

3.01

A.

3.02

A.

CLEANING:

The Contractor may elect to use either high velocity jet, or mechanically powered
equipment, as described in the NASSCO Standard Specifications. Selection of equipment
shall be based upon field conditions such as access to manholes, quantity of debris, size of
sewer, depth of flow, etc.

All sludge, dirt, sand, rocks, grease, and other solid or semisolid material resulting from the
cleaning operation shall be decanted and disposed of at the City landfill, and in a method
acceptable to the Engineer. Pipe cleaning shall be performed in advance of pipe television
inspection.

Acceptance by the Engineer of the cleaning results will be based on the results of television
inspection. If the results are unsatisfactory, the Contractor shall repeat the cleaning until
accepted by the Engineer at no additional cost to the Owner.

CLOSED-CIRCUIT TELEVISION (CCTV) INSPECTION:

Closed-circuit television (CCTV) inspection shall be done one manhole section at a time,
and the section being inspected shall be suitably isolated from the remainder of the sewer
line as required. No sanitary sewer lines shall be inspected until they have been cleaned.
The camera shall be moved through the line in either direction at a uniform slow rate,
stopping when necessary to insure proper documentation of the sewer's condition, but in no
case will the television camera be pulled at a speed greater than 30 feet per minute.

Measurement for location of defects shall be accurately measured from the starting
manhole by a metering device mounted on the camera or by other means acceptable to
the Engineer. Marking on cable, or the like, which would require interpolation for depth
of manhole, will not be allowed. Measurement meters will be accurate to 0.2 feet. A

2019 Sewer Replacement Project Cleaning and Television Inspection of Pipelines
Nashua, NH 02441-2

measuring target (or the sealing packer) in front of the television shall be used as an exact
measurement reference point, and the meter reading shall show this exact location of the
measurement reference point.

E. Electronic video equipment shall be capable of displaying and recording, at a minimum,
the following data for each pipe joint:

1. Project Identification

2. Date recorded

3. Footage counter

4. Sewer reach identification (street location, start MH and second MH)

3.03 DOCUMENTATION:

A. _ Printed location records shall be kept by the Contractor which will clearly show the exact
location, in relation to adjacent manholes, of each defect discovered by the television
camera. In addition, other points of significance such as locations of laterals, unusual
conditions, collapsed sections, and other discernible features will be recorded and a copy of
such records will be supplied to the Engineer.

B. _ Instant developing of standard size digital photographs of the television monitor at problem
areas shall be taken by the Contractor on the request of the Engineer, so long as such
photographing does not interfere with the Contractor's operations.

C. Digital files of the entire inspection shall be provided to the Engineer upon completion
of the inspection. The playback shall be at the speed that it was recorded.
The Contractor shall be required to have all digital files and necessary playback
equipment readily accessible for review by the Engineer during the project.

D. The Contractor shall furnish printed internal inspection logs and two (2) DVD discs of the
entire inspection to the Engineer on completion.

END OF SECTION

2019 Sewer Replacement Project Cleaning and Television Inspection of Pipelines
Nashua, NH 02441-3

SECTION 02451

FLAGGERS AND UNIFORMED OFFICERS FOR TRAFFIC CONTROL

PART 1 - GENERAL
1.01 WORK INCLUDED:

A. _ This Section covers the provisions for furnishing Flaggers and Uniformed Police Officers
for Maintenance of Traffic as described in Section 01110 CONTROL OF WORK AND
MATERIALS, to direct traffic through or around work as shown on the plans or as ordered by the

Engineer.
1.02 DESCRIPTION:
A. The Contractor shall coordinate with the Engineer to determine the number of Flaggers

and Officers deemed necessary to provide for public safety and to maintain a smooth flow
of traffic through the construction area(s) affected.

1.03 RELATED WORK:

A. SECTION 01110, CONTROL OF WORK AND MATERIALS
PART 2 - PRODUCTS
2.01 | UNIFORMED POLICE OFFICERS:

A. — Contractor shall provide the Traffic Control Officer with a minimum of 24 hours notice
indicating the time of day, street location and confirm number of officers required for
traffic control. This shall be as agreed by the Engineer. The Contractor may furnish
additional traffic control personnel at his/her own expenses but only those agreed upon by
the Engineer will be measured for payment.

B. Contractor shall give the Traffic Control Officer a minimum of 2 hours prior cancellation
notice should Contractor determine that due to weather or conditions beyond his control he
would not need the scheduled officers.

C. Contractor shall pay for officer(s) at the prevailing rate established by the local police
department should officers not be needed and the Contractor fails to cancel the officers as
noted in 2.01.B above.

2019 Sewer Replacement Project Flaggers and Uniformed Officers for Traffic Control
Nashua, NH 02451-1