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J. The Contractor shall build a tight bulkhead in the pipeline where new work enters an existing
sewer. This bulkhead shall remain in place until its removal is authorized by the Engineer.

K. Care shall be taken to prevent earth, water, and other materials from entering the pipe, and when
pipe laying operations are suspended, the Contractor shall maintain a suitable stopper in the end
of the pipe and also at openings for manholes.

L. _ Assoonas possible after the pipe and manholes are completed on any street, the Contractor shall
flush out the new pipeline using a rubber ball ahead of the water, and none of the flushing water
or debris shall be permitted to enter any existing sewer.

3.02 QUALITY ASSURANCE

A. CLEANING, INSPECTION, AND TESTING:

1.

On completion of a section of sewer, the Contractor shall TV inspect the main section in
accordance with Section 02441, Cleaning, Television Inspection, and Testing of New
Pipelines at no additional cost to the Owner.

The Contractor shall be responsible for the satisfactory water-tightness of the entire
section of the sewer. Should the Engineer determine that the sections inspected are not
satisfactory, the Contractor shall be required to excavate and replace the entire section, at
no additional cost to the Owner.

B. PIPE DEFLECTION MEASUREMENT:

1.

2.

In accordance with ASTM D3034, no less than 30 days after completion of the PVC sewer
pipe installation, the Contractor shall test the pipeline for deflection using a "go/no-go"
deflection mandrel having a minimum of nine evenly spaced arms or prongs. The
"go/no-go" gauge shall be hand pulled through all sections of the pipeline by the
Contractor. The Contractor shall submit drawings of the "go/no-go" gauge to the Engineer
for approval prior to testing. Complete dimensions of the gauge for each diameter of pipe
to be tested shall be in accordance with ASTM D3034.

Any section of pipe found to exceed 7.5 percent deflection shall be deemed a failed pipe

and shall be excavated and replaced by the Contractor at his own expense.

END OF SECTION

2019 CIPPLining Project Polyvinyl Chloride Gravity Pipe and Fittings

Nashua, NH

02085-4

SECTION 02252

SUPPORT OF EXCAVATION
PART 1 - GENERAL
1.01 WORK INCLUDED:
A. This section of the specification covers sheeting and bracing for support of

excavations. The requirements of this section shall also apply, as appropriate, to other
methods of excavation support and underpinning which the Contractor elects to use to
complete the work.

B. The Contractor shall furnish and place sheeting of the kinds and dimensions required,
complying with these specifications, where indicated on the drawings or ordered by the
Engineer.

1.02 RELATED WORK:
A. Section 02300, EARTHWORK.

1.03 QUALITY ASSURANCE:

A. _ This project is subject to the Safety and Health regulations of the U.S. Department of Labor
set forth in 29 CFR, Part 1926, and to New Hampshire law, RSA, Title XXIII: Labor.
Contractors shall be familiar with the requirements of these regulations.

B. The excavation support system shall be of sufficient strength and be provided with
adequate bracing to support all loads to which it will be subjected. The excavation support
system shall be designed to prevent any movement of earth that would diminish the width of
the excavation or damage or endanger adjacent structures.

PART 2 - PRODUCTS

2.01 MATERIALS:

A. Steel used for bracing shall be of such size and strength as required in the excavation
support design. Timber or steel used for bracing shall be new or undamaged used material
which does not contain splices, cutouts, patches, or other alterations which would impair its
structural integrity or strength.

PART 3 ~EXECUTION

3.01 INSTALLATION:

2019 CIPPLining Project Support of Excavation
Nashua, NH 02252-1

A,

Work shall not be started until all materials and equipment necessary for their construction are
either on the site of the work or satisfactorily available for immediate use as required.

The sheeting shall be securely and satisfactorily braced to withstand all pressures to which it
may be subjected and be sufficiently tight to minimize lowering of the groundwater level
outside the excavation.

No sheeting may be left so as to create a possible hazard to safety of the public or a
hindrance to traffic of any kind.

If boulders or very dense soils are encountered, making it impractical to drive a section to the
desired depth, the section shall be cut off.

The sheeting shall be left in place where indicated on the drawings or ordered by the
Engineer in writing. At all other locations, the sheeting may be left in place or salvaged at
the option of the Engineer. Steel sheeting permanently left in place shall be cut off at a depth
of not less than two feet below finish grade unless otherwise directed.

All cut-off will become the property of the Contractor and shall be removed by him from the
site.

Sole responsibility for the satisfactory construction and maintenance of the excavation
support system, complete in place, shall rest with the Contractor. Any work done,
including incidental construction, which is not acceptable for the intended purpose shall
be either repaired or removed and reconstructed by the Contractor at his expense.

The Contractor shall be solely responsible for repairing all damage associated with
installation, performance, and removal of the excavation support system.

END OF SECTION

2019 CIPPLining Project Support of Excavation
Nashua, NH 02252-2

SECTION 02300

EARTHWORK

PART 1 - GENERAL
1.01 WORK INCLUDED:

The Contractor shall make excavations of normal depth in earth for trenches and structures,
shall backfill and compact such excavations to the extent necessary, shall furnish the
necessary material and construct embankments and fills, and shall make miscellaneous
earth excavations and do miscellaneous grading.

1.02 RELATED WORK:
A. Section 01110, CONTROL OF WORK AND MATERIALS
B. Section 02085, POLY VINYL CHLORIDE GRAVITY PIPE AND FITTINGS
C. Section 02252, SUPPORT OF EXCAVATION

D. Section 02745, ROAD RESTORATION

1.03 REFERENCES:
American Society for Testing and Materials (ASTM)

ASTM C131 Test Method for Resistance to Degradation of Small Size Coarse
Aggregate by Abrasion and Impact in the Los Angeles Machine.

ASTM C136 ~~ Method for Sieve Analysis of Fine and Coarse Aggregates.

ASTM C330 Specification for Lightweight Aggregate for
Structural Concrete.

ASTM D1556 Test Method for Density of Soil in Place by the Sand Cone
Method.

ASTM = D1557 Test Methods for Moisture-density Relations of Soils and Soil

Aggregate Mixtures Using Ten-pound (10 Lb.) Hammer and
Eighteen-inch (18") Drop.

ASTM = D2922 Test Methods for Density of Soil and Soil-aggregate in Place by
Nuclear Methods (Shallow Depth).

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

2019 CIPP Lining Project Earthwork
Nashua, NH 02300-1

Material test results performed by a certified laboratory shall be submitted to the
Engineer for all materials proposed for use on the project. If required by the Engineer,
samples shall be submitted for independent testing.

1.05 PROTECTION OF EXISTING PROPERTY:

A. The work shall be executed in such manner as to prevent any damage to facilities at the site
and adjacent property and existing improvements, such as but not limited to streets, curbs,
paving, service utility lines, structures, monuments, bench marks, observation wells,
and other public or private property. Protect existing improvements from damage
caused by settlement, lateral movements, undermining, washout and other hazards
created by earthwork operations.

B. Incase of any damage or injury caused in the performance of the work, the Contractor
shall, at its own expense, make good such damage or injury to the satisfaction of, and
without cost to, the Owner. Existing roads, sidewalks, and curbs damaged during the
project work shall be repaired or replaced to at least the condition that existed at the start
of operations. The Contractor shall replace, at his own cost, existing benchmarks,
observation wells, monuments, and other reference points which are disturbed or
destroyed.

C. Buried drainage structures and pipes, observation wells and piezometers, including those
which project less than eighteen inches (18") above grade, which are subject to damage
from construction equipment shall be clearly marked to indicate the hazard. Markers shall
indicate limits of danger areas, by means which will be clearly visible to operators of trucks
and other construction equipment, and shall be maintained at all times until completion
of project.

1.06 DRAINAGE:

A. The Contractor shall provide, at its own expense, adequate drainage facilities to complete
all work items in an acceptable manner. Drainage shall be done in a manner so that runoff
will not adversely affect construction procedures or cause excessive disturbance of
underlying natural ground or abutting properties.

1.07 FROST PROTECTION AND SNOW REMOVAL:

A. The Contractor shall, at its own expense, keep earthwork operations clear and free of
accumulations of snow as required to carry out the work.

B. The Contractor shall protect the sub-grade beneath new structures and pipes from frost
penetration when freezing temperatures are expected.

PART 2 - PRODUCTS
2.01 MATERIAL:
A. GRAVEL BORROW:
Gravel borrow shall consist of inert material that is hard, durable stone and coarse

2019 CIPP Lining Project Earthwork
Nashua, NH 02300-2

sand essentially free of organic matter, plastic fines (clay) and debris, and shall
meet the gradation requirements below:

Sieve Opening Percent Passing (weight)
6 inch 100
No 4 25 - 70
No 200 0-12

B. CRUSHED GRAVEL:

The Gravel Road Base will be NHDOT - Item 304.3 Crushed Gravel, or Item
304.4 Crushed Stone (Fine Gradation).

C. BACKFILL MATERIALS:
1. Class B Backfill:

Class B backfill shall be granular, well graded friable soil; free of rubbish, ice,
snow, tree stumps, roots, clay and organic matter; with 30 percent or less passing
the No. 200 sieve; no stone greater than two-third (2/3) loose lift thickness, or
six inches, whichever is smaller.

2. Select Backfill:

Select backfill shall be granular, well graded friable soil, free of rubbish, ice,
snow, tree stumps, roots, clay and organic matter, and other deleterious or
organic material; graded within the following limits:

Sieve Size Percent Finer by Weight
3” 100
No. 10 30 - 95
No. 40 10-70
No. 200 0-10

D. SEWER PIPE BEDDING MATERIAL

1. Sewer pipe bedding material shall be screened gravel or crushed stone meeting
the ASTM C33/C33M stone size No. 67..

2. Sand blanket material for sewer pipe shall be graded sand free from organic
materials, graded such that 100 percent passes a “4-inch sieve and a maximum of
15 percent passes a #200 sieve.

PART 3 — EXECUTION

3.01 DISTURBANCE OF EXCAVATED AND FILLED AREAS

2019 CIPP Lining Project Earthwork
Nashua, NH 02300-3

DURING CONSTRUCTION:

A. Contractor shall take the necessary steps to avoid disturbance of sub-grade during
excavation and filling operations, including restricting the use of certain types of
construction equipment and their movement over sensitive or unstable materials,
dewatering and other acceptable contro] measures.

B. All excavated or filled areas disturbed during construction, all loose or saturated soil,
and other areas that will not meet compaction requirements as specified herein shall
be removed and replaced with a minimum 12-inch layer of compacted crushed stone
wrapped all around in non-woven filter fabric. Costs of removal and replacement
shall be borne by the Contractor.

C. The Contractor shall place a minimum of 12-inch layer of special bedding materials
and crushed stone wrapped in filter fabric over the natural underlying soil to
stabilize areas which may become disturbed as a result of rain, surface water runoff
or groundwater seepage pressures, all at no additional cost to the Owner. The
Contractor also has the option of drying materials in-place and compacting to
specified densities

3.02 EXCAVATION:

A. GENERAL:

1. The Contractor shall perform all work of any nature and description required
to accomplish the work as shown on the Drawings and as specified.

2. Excavations, unless otherwise required by the Engineer, shall be carried only
to the depths and limits shown on the Drawings. If unauthorized excavation is
carried out below required sub-grade and/or beyond minimum lateral limits
shown on Drawings, it shall be backfilled with gravel borrow and compacted
at the Contractor's expense as specified below, except as otherwise indicated.
Excavations shall be kept in dry and good conditions at all times, and all voids
shall be filled to the satisfaction of the Engineer.

3. In all excavation areas, the Contractor shall strip the surface topsoil layer and
underlying subsoil layer separate from underlying soils. In paved areas, the
Contractor shall first cut pavement as specified in paragraph 3.02 B.1 of this
specification, strip pavement and pavement sub-base separately from
underlying soils. All excavated materials shall be stockpiled separately from
each other within the limits of work.

4. The Contractor shall follow a construction procedure, which permits visual
identification of stable natural ground. Where groundwater is encountered, the
size of the open excavation shall be limited to that which can be handled by the
Contractor's chosen method of dewatering and which will allow visual
observation of the bottom and backfill in the dry.

5. The Contractor shall excavate unsuitable materials to stable natural ground
where encountered at proposed excavation sub-grade, as directed by the
Engineer. Unsuitable material includes topsoil, loam, peat, other organic
materials, snow, ice, and trash. Unless specified elsewhere or otherwise

2019 CIPP Lining Project Earthwork
Nashua, NH 02300-4

carry out and perform in accordance with the terms and conditions of the contract the work described.

3. PERIOD OF PERFORMANCE. Professional Engineer shall perform and complete all work by January 09,
2023 which date shall only be altered by mutually approved written agreement to extend the period of
performance or by termination in accordance with the terms of the contract. Professional Engineer shall
begin performance upon receipt of an Executed Contract and a valid Purchase Order issued from the City

of Nashua.

4. COMPENSATION. Professional Engineer agrees to perform the work for a total cost not to exceed
Dollars ($404,340.00 )

The Contract Sum shall include all items and services necessary for the proper execution and completion
of the Work.

Unless Professional Engineer has received a written exemption from the City of Nashua, Professional
Engineer shall submit monthly requests for payment for services performed under this agreement in
accordance with the values stated in the Agreement. Such requests shall be supported by such data
substantiating the Professional Engineer’s right to payment as the City of Nashua may reasonably require.
Professional Engineer shall submit monthly requests for payment for services performed under this
agreement shall be submitted as follows:

> Electronically via email to VendorAPInvoices(@NashuaNH.gov

OR

> Paper Copies via US Mail to:

City of Nashua, City Hall
Accounts Payable

229 Main Street

Nashua, NH 03060

Please do not submit invoices both electronically and paper copy.

In addition, and to facilitate the proper and timely payment of applications, the City of Nashua requires
that all submitted invoices contain a valid PURCHASE ORDER NUMBER.

Requests for payment shall be submitted no later than fifteen (15) days after the end of each month and
must include a detailed summary of the expenditures reported in a form that supports the approved budget.
Specifically, Professional Engineer agrees to provide the following with each request for payment:

1. Appropriate invoice forms. The forms shall include the project purchase order number, a listing
of personnel hours and billing rates, and other expenditures for which payment is sought.

2. A progress report. The report shall include, for each monthly reporting period, a description of
the work accomplished, problems experienced, upcoming work, any extra work carried out, and a
schedule showing actual expenditures billed for the period, cumulative total expenditures billed
and paid to date under the contract, and a comparison of cumulative total expenditures billed and

paid to the approved budget.

The City of Nashua will pay for work satisfactorily completed by Professional Engineer. The City of
Nashua will pay Professional Engineer within 30 days of approval by the City of Nashua of the submitted
invoice forms and progress reports. The City of Nashua will make no payments until the invoice forms and

progress reports have been submitted and approved.

AG 2 of 3

directed by the Engineer, areas where unsuitable materials have been
excavated to stable ground shall be backfilled with compacted special bedding
materials or crushed stone wrapped all around in non-woven filter fabric.

B. TRENCHES:

1.

Prior to excavation, trenches in pavement shall have the traveled way surface
cut in a straight line by a concrete saw or equivalent method, to the full depth
of pavement. Excavation shall only be between these cuts. Excavation support
shall be provided as required to avoid undermining of pavement. Cutting
operations shall not be done by ripping equipment.

Trenches shall be excavated to such depths as will permit the pipe to be laid at
the elevations, slopes, and depths of cover indicated on the Drawings. Trench
widths shall be as shown on the Drawings or as specified.

Where pipe is to be laid in bedding material, the trench may be excavated by
machinery to, or just below, the designated sub-grade provided that the
material remaining in the bottom of the trench is not disturbed.

If pipe is to be laid in embankments or other recently filled areas, the fill
material shall first be placed to a height of at least 12-inches above the top of
the pipe before excavation.

Pipe trenches shall be made as narrow as practicable and shall not be widened
by scraping or loosening materials from the sides. Every effort shall be made
to keep the sides of the trenches firm and undisturbed until backfilling has
been completed.

If, in the opinion of the Engineer, the sub-grade, during trench excavation, has
been disturbed as a result of rain, surface water runoff or groundwater seepage
pressures, the Contractor shall remove such disturbed sub-grade to a minimum
of 12 inches and replace with crushed stone wrapped in filter fabric. Cost of
removal and replacement shall be borne by the Contractor.

C. BUILDING AND FOUNDATION EXCAVATION:

I.

2.

Excavations shall not be wider than required to set, brace, and remove forms
for concrete, or perform other necessary work.

After the excavation has been made, and before forms are set for footings, mats,
slabs, or other structures, and before reinforcing is placed, all loose or
disturbed material shall be removed from the sub-grade. The bearing surface
shall then be compacted to meet the requirements of this specification.

If, in the opinion of the Engineer, the existing material at sub-grade elevation is
unsuitable for structural support, the Contractor shall excavate and dispose of
the unsuitable material to the required width and depth as directed by the
Engineer. If, in the opinion of the Engineer, filter fabric is required; the
Contractor shall place filter fabric, approved by the Engineer, as per
manufacturer's recommendations. Crushed stone shall then be placed in lifts
and compacted to required densities. Backfill shall be placed to the bottom of
the proposed excavation.

2019 CIPP Lining Project Earthwork

Nashua, NH

02300-5

D. EXCAVATION NEAR EXISTING STRUCTURES:

1.

Attention is directed to the fact that there are pipes, manholes, drains, and
other utilities in certain locations. An attempt has been made to locate all
utilities on the drawings, but the completeness or accuracy of the given
information is not guaranteed.

As the excavation approaches pipes, conduits, or other underground structures,
digging by machinery shall be discontinued and excavation shall be done by
means of hand tools, as required. Such manual excavation, when incidental to
normal excavation, shall be included in the work to be done under items
involving normal excavation.

Where determination of the exact location of a pipe or other underground
structure is necessary for properly performing the work, the Contractor shall
excavate test pits to determine the locations.

3.03 BACKFILL PLACEMENT AND COMPACTION:

A. GENERAL:

l.

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

2019 CIPP Lining Project Earthwork

Nashua, NH

02300-6