EXHIBIT A
SCOPE OF SERVICES
City of Nashua, New Hampshire
Division of Public Works
Wastewater Treatment Facility
Revision of Capacity Analysis
ee TT
Hazen and Sawyer, P.C. will perform professional engineering services in conjunction with revising the
capacity analysis of the Nashua Wastewater Treatment Facility (WWTF) that was performed in 2013 and
2014. The project is in response to effluent limitations defined in NPDES permit NHO100170 and possible
future flaws and loads to the plant. An amendment to the existing capacity technical memorandum will
be prepared summarizing the results of the revised analysis.
SCOPE OF WORK
Task 1 — Historical Data Review and Data Collection
Hazen and Sawyer will:
« Conduct data review of historical data for the period June 2014 through June 2016. This effort
will be used to revise findings from the data summary performed as part of the 2013/2014
capacity analyses.
» Updated data will be used to revise influent wastewater characteristics and peaking factors.
* Maximum one (1) day in the field to collect updated solids data at the Nashua WW'TF for use
in the model update and analysis, as required.
Task 2 — Plant Analysis
Hazen and Sawyer will use the updated data from Task 1 to perform updated capacity
evaluations on liquids and solids process at the WWTF. The processes that will be included in the
evaluation will be limited to:
1) Aeration tanks,
2) Aeration system,
3) Secondary clarifiers,
4) Primary anaerobic digester.
Updates to existing planning level cost estimates for infrastructure modification will not be
provided in this effort.
Task 3 - Draft and Final Report and Workshop
Hazen and Sawyer will develop an amendment to the existing capacity technical memorandum.
The amendment will provide information regarding the revised capacity of each unit process and
the overall WWITF capacity under current design conditions.
Nashua Capacity Analysis Revision Contract Exhibit A- Scape of Work-NJE + FIA docx
Page 1 of 2
