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3.09

FINAL CLEANING AND DECONTAMINATION

This Subsection applies to the final cleaning of all work areas where asbestos has been
removed. After all Asbestos-Containing (or contaminated) Materials have been
removed, the Contractor shall remove all wastes and perform a thorough multi-stage
final cleanup and decontamination of each Work Area. Final cleaning shall be
performed only after all waste is packaged and removed, but prior to dismantling any
barrier, Decontamination Facility, or protective coverings. Work Area must be Certified
Clean by the Engineer as described herein based on a visual inspection and air testing.
Substrate cleanliness may also be confirmed via collection of bulk samples for analysis
via Polarized Light Microscopy and / or Transmission Electron Microscopy, 1f required
by the Engineer (see also Subsection 1.03.A.12). All HEPA Filtered Exhaust Units shall
operate continuously throughout the cleaning and air testing processes until the Engineer
agrees to their shutdown and removal from the site. The Contractor shall notify the
Engineer in writing at least 12 hours in advance of the expected completion time of site
cleaning in order to allow the Engineer to schedule air clearance testing.

Methods and Approvals: Cleaning methods shall be specified in the Contractor’s Plan
of Action & Standard Operating Procedures. Approvals and sequencing shall consist of
the following:

1. Remove all visible accumulations of debris on the protective coverings on floors,
walls, and other surfaces, and then HEPA vacuum all surfaces to pick up excess
water and gross saturated debris.

2. After HEPA-vacuuming, the Work Area air shall be lightly misted, and then all
protective coverings on ceilings, walls, floors, and other items in the Work Area
shall be wiped thoroughly clean.

3. After the Contractor has completed the above steps (1) and (2), Contractor shall
request the Engineer to inspect the site.

4. If the Engineer observes any debris within the Work Area during the inspection,
the Contractor shall perform additional cleanup and decontamination, as
necessary, until the Engineer accepts the work (acceptance of the cleanliness of
the work area is based solely on industry standards). However, the critical barrier
walls, Decontamination Facilities, HEPA Filtered Exhaust Units, and primary
isolation seals shall remain in place and in use.

5. After the Engineer accepts the cleaning, the Contractor shall apply penetrating
Encapsulant to all surfaces within the Work Area. The Encapsulant shall then be
allowed to dry and after the Engineer's review, slowly remove the upper layer of
all protective poly coverings on walls and other surfaces and package them in
Disposal Bags. These Disposal Bags shall then be removed from the Work Area

02111-44

3.10

following the procedures described herein. The bottom layer of protective poly
coverings, the Decontamination Facilities, the HEPA exhaust systems and all
barrier walls shall remain in place and in use.

AIR MONITORING BY ENGINEER

This Subsection describes air monitoring carried out by the Engineer to verify that the
areas beyond the Work Area or Regulated Area and the outside environment remain
uncontaminated. This Subsection also sets forth airborne fiber levels both inside and
outside the Work Area or Regulated Area as action levels, and describes the action
required by the Contractor if an action level is met or exceeded. The Engineer will be
conducting air monitoring throughout the course of the Work in accordance with all
applicable regulations.

All perimeter sampling and analysis will be performed by the Engineer. Written reports
of all air monitoring tests will be posted at the job site on a daily basis.

Personnel air monitoring required by OSHA 1s the responsibility of the Contractor and is
not covered in this Subsection.

Work Area Isolation: The purpose of the Engineer's air monitoring will be to detect
faults in the Work Area isolation such as:

° Contamination of areas outside of the Work Area with airborne asbestos fibers,
° Failure of filtration or rupture in the negative pressure system,
° Upon notification by the Engineer that an Action Level, or any of the above has

been exceeded, the Contractor shall immediately cease asbestos Abatement
Activities until the fault 1s corrected. Work shall not recommence until
authorized by the Engineer.

Final Air Clearance Testing: To determine if the elevated airborne fiber counts
encountered during abatement operations have been reduced to an acceptable level, the
Engineer will sample and analyze air per Subsection 3.12.

Airborne Fiber Counts:

1. Inside Work Area: The Contractor shall maintain an average airborne fiber
concentration in the Work Area of less than 0.5 fibers per cubic centimeter. Ifthe
fiber concentration rises above this figure for any sample taken, revise work
procedures to lower fiber concentration. If the Time Weighted Average (TWA)
fiber count for any work shift or 8 hour period exceeds 0.5 fibers per cubic
centimeter, stop all work, leave negative air system in operation and notify
Engineer. Do not recommence work until authorized in writing by Engineer.

02111-45

3.11

If airborne fiber concentrations exceed 2.0 fibers per cubic centimeter for any
period of time, cease all Work until fiber counts fall below 0.5 fibers per cubic
centimeter and notify Engineer. Do not recommence Work until authorized in
writing by the Engineer.

2. Outside Work Area: If any air sample taken outside of the Work Area exceeds
the established baseline, immediately and automatically stop all Work.

a. Decontaminate the affected area in accordance with these Specifications.

b. Respiratory protection shall be worn in affected area until area is cleared
for reoccupancy.

C. Leave critical barriers in place until completion of Work.

d. If the exit from the Clean Room of the personnel Decontamination Unit
enters the affected area, establish a temporary Decontamination Facility
consisting of a Shower Room and Changing Room as specified herein.
After cleaning and decontamination of the affected area remove the
Shower Room and leave the Changing Room in place as an Air Lock.

e. After certification of visual inspection 1n the Work Area remove critical
barriers separating the Work Area from the affected area. Final air
samples will be taken within the entire area as set forth in Subsection 3.12.

Fiber Counts: The following procedure will be used to resolve any disputes regarding
fiber types when a project has been stopped due to excessive airborne fiber counts.
"Airborne Fibers" referred to above include all fibers regardless of composition as
counted in the NIOSH 7400 Procedure. If Work has stopped due to high airborne fiber
counts, air samples will be secured in the same area by the Department for analysis by
electron microscopy. "Airborne Fibers" counted in samples analyzed by Transmission
Electron Microscopy (TEM) shall be only asbestos fibers, but of any diameter and
length. TEM analysis shall be performed according to 40 CFR Part 763 Subpart M,
Appendix E.

AIR MONITORING BY CONTRACTOR

The Contractor shall perform air monitoring as required to meet OSHA requirements for
maintenance of Time Weighted Average (TWA) fiber concentrations for types of
respiratory protection provided. The Engineer will not be performing air monitoring to
meet these OSHA requirements.

The sampling person and analysis laboratory performing this Work shall be an
independent party not financially or managerially connected to the Contractor.

02111-46

3.12

The laboratory shall be successfully participating in the AIHA/NIOSH Proficiency
Analytical Testing (PAT) program and be Certified by the State of New Hampshire.

Numbers and frequencies of personal air sampling shall be as required by OSHA
regulations but not less than one (1) sample per eight (8) hour work shift during times of
asbestos removal and related work.

Results of sample analysis shall be provided to the Engineer within twenty-four (24)
hours of collection.

The Contractor shall provide a pre-approved "chain-of-custody" form for all personal air
samples collected.

FINAL WORK AREA CLEARANCE

The final air clearance testing shall take place using aggressive air sampling techniques.

The Contractor shall supply and operate circulating fans and leaf blowers as directed by
the Engineer during this final testing to ensure effective air circulation. The final test
shall consist of taking air samples in the Work Area to establish that contamination
levels do not exceed 0.01 f/cc or the established baseline as determined by NIOSH
Method 7400 (Phase Contrast Microscopy).

The Department may require final air clearance testing by the method specified in 40
CFR Part 763, Subpart E, Appendix A (Transmission Electron Microscopy).

Surface wipes and/or bulk samples may also be taken and analyzed at the option of the
Engineer to confirm that all microscopically detectable asbestos has been removed.
Analysis will be performed using approved EPA methods, including but not limited to,
Method 600/M4-82-920 for bulk asbestos sample analysis.

If the results of any of the final testing as described herein are not satisfactory, thorough
wet cleaning and/or HEPA vacuuming shall be repeated until the required
decontamination levels are achieved. The Contractor shall bear all costs for additional
cleaning until the area passes final Work Area clearance.

After achieving the level of cleanliness and decontamination, as specified herein and as
confirmed by the final inspections and testing, the Contractor will be notified of Work
Area clearance.

After successful completion of the final air clearance testing, the Contractor shall
carefully remove the Decontamination Facilities and any temporary barrier walls or
tunnels. The HEPA-exhaust systems shall be removed only after all other items are
removed. A sufficient number of HEPA-vacuum shall be kept on-site during this final
disassembly work to cleanup any dust or debris.

END OF SECTION

02111-47

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 1s 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 XXII: 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:

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.

02252-1

B. _ 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.

C. The sheeting shall be driven by approved means to the design elevation. 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.

D. Ifboulders or very dense soils are encountered, making it impractical to drive a section to the
desired depth, the section shall, as directed, be cut off.

E. 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.

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

G. _ 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.

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

END OF SECTION

02252-2

SECTION 02300

EARTHWORK

PART 1 - GENERAL

1.01

1.02

595 AO BD }

es

1.03

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.

RELATED WORK:

Section 01110, CONTROL OF WORK AND MATERIALS
Section 01570, ENVIRONMENTAL PROTECTION
Section 02252, SUPPORT OF EXCAVATION

Section 02324, ROCK EXCAVATION AND DISPOSAL
Section 02745, PAVING

Section 02920, LOAMING AND SEEDING

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).

02300-1

1.04

1.05

1.06

1.07

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

Samples of all materials proposed for the project shall be submitted to the Engineer for
review. Size of the samples shall be as approved by the Engineer.

PROTECTION OF EXISTING PROPERTY:

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.

In case 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.

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.

DRAINAGE:

The Contractor shall provide, at its own expense, adequate drainage facilities to complete
all work ttems 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.

FROST PROTECTION AND SNOW REMOVAL:

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

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

02300-2

PART 2 - PRODUCTS
2.01 MATERIAL:
A. GRAVEL BORROW:
Gravel borrow shall consist of inert material that is hard, durable stone and coarse
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 STONE:
Crushed stone shall consist of sound, hard, durable, angular fragments obtained
by breaking and crushing solid or shattered natural rock. Crushed stone shall not
contain vegetation, masses of roots, loam and other organic matter, clay, and
other fine or harmful substances. It shall be well graded and shall meet the
gradation requirements listed below:

Sieve Opening Percent Passing
2 inch 100

1-1/2 inch 85 - 100

3/4 inch 45-75

No. 4 10 - 45

No. 200 0-5

C. SAND BORROW:

The maximum size of any stone or fragment shall not exceed three-fourths of the
compacted depth of the layer being placed but in no case larger than 6 inches

Passing No. 4 sieve opening 70 — 100%
Passing No. 200 sieve opening O-12%

E. PEASTONE:

Peastone shall be smooth, hard, naturally occurring, rounded stone meeting the
following gradation requirements:

Passing 5/8 inch square sieve opening - 100%

Passing No. 8 sieve opening - 0%

E. 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

02300-3

City of Nashua

Purchasing Department
Administrative Services Division (603) 589-3330
229 Main Street - Nashua, NH 03060 Fax (608) 594-3233

September 1, 2022
Memo #23-323

TO: Mayor Donchess
Finance Committee

SUBJECT: 2022 Sewer Rehabilitation in the amount not to exceed $1,173,000 funded from 81700
Infrastructure Improvements/Bond

Please see attached communications from Daniel Hudson, City Engineer, dated July 28, 2022 for project
specific details related to this purchase. Below please find a summary of the purchase approval request:

Item: Siphon Rehabilitation Construction using cured-in-place pipe lining
Value: $1,173,000
Vendor: Insituform Technologies LLC

Department: 169 Wastewater
Source Fund: 81700 Infrastructure Improvements/ Bond

Ordinance: Pursuant to § 5-78 Major purchases (greater than $25,000) A. All supplies and
contractual services, except as otherwise provided herein, when the estimated cost thereof shall exceed
$25,000 shall be purchased by formal, written contract from the lowest responsible bidder, after due
notice inviting bids.

A competitive bid IFB 0779-071422 for this project was issued on June 14, 2022 and the following
proposals/bids were received:

Vendor Location Amount Note
Insituform Technologies LLC Chesterfield, MO | $1,173,000.00

National Water Main Boston, MA $1,337,750.00

Cleaning Co.

The Board of Public Works (08/25/2022 BPW meeting), Division of Public Works: Wastewater,
and the Purchasing Department respectfully request your approval of this contract.

Regards,

Amy Girard

Purchasing Manager

Cc: D Hudson
C O'Connor
K Kleiner