September 10, 2021 Page 4
20210910 Bridge St E Hollis St Nashua Sanborn Head Amend 1.docx 4381.00
Task FD2 - Asbestos Disposal Site Work Plan
In the event that the environmental field exploration identifies asbestos-containing soil in
the project area, Sanborn Head will prepare a project-specific ADS Work Plan for approval
by the NHDES to comply with the state asbestos regulations in Env-Sw 2100. The ADS
Work Plan will include the information required by the regulations such as contact
information for the City, project description, schedule, summary of work, required
qualifications and training for project personnel, health and safety procedures for handling
of asbestos-contaminated soils during construction, and project notifications and
reporting. The ADS Work Plan, if needed, will become part of the bid documents for the
project.
In estimating the level of effort required for the ADS Work Plan, we assume that the volume
of asbestos-contaminated soil in the project area is limited such that asbestos-
contaminated soil encountered will be disposed off-site at the City’s Four Hills Landfill,
which is permitted to receive asbestos contaminated material. We did not included costs
for engineering needed for design of permanent on-site asbestos disposal sites within the
right-of-way, nor costs for obtaining a waiver from the NHDES to allow on-site disposal in
the event that the volume of asbestos-contaminated soil is significant. We can provide such
services if needed as an additional service for an additional fee.
Task FD3 - Coordination with NHDES on ADS Work Plan
We included an allowance of 20 hours for coordination with the NHDES during review of
the ADS Work Plan and responding to their comments to achieve approval of the ADS Work
Plan.
Task FD4 - Geotechnical Subsurface Exploration and Laboratory Testing
Prior to the geotechnical subsurface explorations, we will prepare a proposed geotechnical
boring location plan for review by the project team. Upon acceptance, we will layout the
proposed boring locations in the field and notify DigSafe to obtain utility clearance. Test
boring locations will be selected by Sanborn Head to avoid existing underground utilities,
which may result in certain borings being drilled up to 30 feet from proposed mast arm
foundation locations.
We included three days of geotechnical test borings to complete 6 to 8 test borings to
depths between 15 and 25 feet, and an additional 2 test borings to a depth of 12 feet for 2
borehole infiltration tests. Split-spoon soil samples will be collected at 5-foot depth
intervals or more frequently at the discretion of the geotechnical engineer. We included an
allowance for police details with a cruiser for up to three days during this work.
The test borings will be observed on a full-time basis by an engineer or geologist from
Sanborn Head who will collect soil samples and prepare logs of the subsurface conditions
encountered. We assume this field work will be observed by a New Hampshire Asbestos
Disposal Site Certified Worker.
SANBORN HEAD
