fs NORMANDEAU City of Nashua
BAFE ASSOCIATES Hane 18, 2019
ENVIRONMENTAL CONSULTANTS
© Collect an adequate number of appropriately sized juvenile herring from a location within the
Merrimack River watershed — we have assumed this can be completed in a period of four
evenings.
o PIT-tag a total of 200 juvenile herring and release directly into the power canal at Mine Falls to
evaluate downstream passage.
o Assumes installation and maintenance of a single PIT receiver during the period September-
November.
e Approach 3 - Defer
© Rely on results from the Desktop Impingement/Entrainment Survivability Assessment to
provide insight into the potential for poor turbine passage survival at the Project.
Schedule and Estimated Cost: The juvenile herring passage evaluation should occur during the fall period
(i.e., September-November) when the Project is operating under normal conditions (i.e., no unit outages, etc.).
We propose this study be conducted during the fall of 2020. Three study approaches were described above
which vary based on the monitoring approach utilized. These three approaches vary in responsiveness to the
study objectives provided by the resource agencies. The estimated costs for each level of effort as described
here is $64,571.50 (telemetry study as requested by NHFGD), $30,359.00 (reduced), and SO (propose to not
adopt field study approach until after review of desktop assessment).
Study: Adult Alosine Downstream Passage Assessment and Protection Evaluation
Requestor: NHFGD
Requestor Goal & Objectives:
e Assess the risk of adult herring and shad becoming injured, impinged or entrained in powerhouse
units.
e Estimate turbine survival.
e Estimate effectiveness of downstream fish passage.
e Assess risk of injury or mortality at the spillway and downstream bypass.
e Evaluate potential passage and protection measures.
Agency Recommended Approach:
e Evaluate turbine passage mortality for adult herring and shad using the turbines, downstream bypass
and spillway with the HI-Z balloon tag methodology.
e Conduct a downstream passage alternatives analysis of operational or structural modifications to
potentially minimize injuries/mortality relative to existing conditions.
Suggested Approach:
e Push back on conducting a HI-Z balloon tag study. Downstream passage survival for adult alosines will
be considered as part of the Desktop Impingement/Entrainment Survivability Assessment.
e Push back on conducting a downstream alternatives analysis pending review of proposed adult herring
telemetry study above.
Study: Three Dimensional CFD Modeling in Vicinity of Fishway Entrance
Requestor: NHFGD
Requestor Goal & Objectives:
