Exhibit A - Scope of Services
Nashua, WWITF — Anaerobic Digester ~ Second Heat Exchanger Project
Task A. Design
1} Hold a project kickoff meeting and site visit to confirm existing conditions within the Primary Gallery.
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and review the City’s desired layout and control system requirements. Kick-off meeting and site visit
to include project engineer, design CAD technician; mechanical (HVAC} engineer, and instrumentation
engineer.
a) A-key issue will be to review the feasibility of relocating the existing temperature and pressure
sensor inputs to be upstream and downstream of the piping to/from both heat exchangers versus
the redundancy that would be provided if individual sensors are provided for each heat
exchanger.
b) Assume existing PLCs in existing control panels will be reused for any additional temperature and
pressure sensor inputs.
c} Assume heat exchangers will be set up for the second to be operated as a back-up only, and not
for both heat exchangers to operate concurrently (one for sludge feed and one for sludge
recirculation).
Perform 3-dimensional scanning of the Primary Digester Gallery. This is assumed to be a one-day
effort and will be subcontracted to Matterscan. Deliverables to include access to an electronic 3D
virtual site walk of the photographed facilities as well as a point cloud for CAD drawing development
of existing facilities. Note: Effort will include primary digester stairway to top for separate digester
fan relocation project.
Prepare 30% preliminary design package including the following:
a} Process and instrumentation diagrams of proposed installation with two heat exchangers
including modifications to the hot water feed system.
b) Process plan and sections of the proposed heat exchanger installation, including sludge piping,
hot water and return piping, valving, and other appurtenances.
c) Technical memorandum summarizing the proposed improvements including a functional
description of the intended operation of the updated system with the second neat exchanger.
d) Meet with the City to review the preliminary design package. Address City comments in writing.
Prepare 95% design drawings and specifications. Assume City staff will be responsible for bidding and
contractual documents. The 95% design package will include:
a) Process and instrumentation diagrams of proposed installation with two heat exchangers
including modifications to the hot water feed system.
b) Process plan and sections of the proposed heat exchanger installation, including aii sludge piping,
hot water and return piping, valving, and other appurtenances.
c) Assume electrical design information, such as wiring and conduit from temperature transmitting
sensor / indicator and pressure transmitting sensor / indicator to control panel, will be shown on
Process drawings.
WrIGHT-PreERCE =
Engineering a Beller Environment ]
