March 31, 2022 Page 3
20220331 Lafleur FY 2023-2025 Services Scope.docx
=« Developing engineering drawings that compare the existing landfill topography (as
provided to us in a recent topographic survey) to the currently permitted final landfill
grades;
« Estimating the remaining disposal capacity (airspace) in terms of cubic yards; and
= Calculating the remaining life of the permitted landfill based on the remaining capacity
and the City’s projected waste acceptance rate.
To accomplish the above, Sanborn Head assumes that the City will provide AutoCAD
formatted drawings of the site topography, as well as recent waste receipts. Sanborn Head
will transmit the results of our evaluation in a letter addressed to the City.
Task4 Annual Financial Assurance Update
The NHDES Rules require landfill owners to submit financial assurance updates to NHDES
every third calendar year in order to demonstrate that financial assurance for closure and
long-term monitoring and maintenance (LTMM) is provided for the Four Hills Landfill
(Env-Sw 1400). During the years in which a submittal to NHDES is not required, an
updated closure cost estimate is required to be prepared and kept for the facility's records.
Since the City last submitted an update to NHDES in March 2021, the next submittal to
NHDES will be required in March 2024. Updates prepared during FY 2023 and 2025
should be kept for the facility’s records.
This financial assurance demonstration includes preparation of opinions of closure and
post-closure cost for the currently permitted areas (Phases I, II, and I{I) and calculations to
demonstrate that the City is setting aside funds sufficient for future closure and post-
closure needs.
Sanborn Head will prepare the opinions of cost using the required NHDES forms based on
the permitted closure plan, currently available average unit costs for similar projects,
current costs for monitoring services, published construction cost estimating guides, and
our engineering judgment. We will estimate the remaining life of Phases I, I], and [I] based
on the latest survey update and prepare sinking fund calculations using account balances
provided to us, actual waste tonnage received at the Four Hills Landfill, and the projected
waste tonnage for the remaining estimated life of Phase I, II, and III. The calculations will
demonstrate that the balances for the closure and LTMM accounts are consistent with what
was projected or provide amounts per ton that should be set aside going forward to
provide sufficient funds at the expected date of closure.
Sanborn Head will prepare a letter, addressed to the City, that documents our evaluation,
which will include NHDES Cost Estimate Forms for landfill closure and post-closure care,
and sinking fund calculations.
Task5 General Engineering Services
Sanborn Head’s services under this task will be performed at the City’s request and involve
routine matters of limited scope, such as attending meetings with regulators and providing
design, operation, or air consultation relative the Four Hills Landfill.
SANBORN HEAD
