MPA CONTRACT NO. A310-C1
FLOOD RESILIENCY PERMANENT IMPROVEMENTS
BOSTON LOGAN INTERNATIONAL AIRPORT,
CONLEY TERMINAL AND FISH PIER
EAST AND SOUTH BOSTON, MA
RESPONSES TO QUESTIONS
MAY 3, 2016
The attention of Contractors submitting General Bids and/or Files Sub-Bids for the above
references project to the following Responses to Questions and/or RFI’s.
Losordo Electric Services, email from Al Oster dated April 27, 2016
Summary of Question: The drawings indicate that the cable sets to be provided are based on
1200 amps and that the generator shall be connected to ATS-1, ATS-2, and ATS-3, but does
not indicate what size feeder shall be run to each.
Assuming that we are to match the permanent wiring and bring 300 amps to ATS-1, 100
amps to ATS-2, and 150 amps to ATS-3; Is the temp generator set up to split up the loads
this way, or will we need to supply a weather rated distribution panel?
The chart on required cables and pigtails listed as Detail 5 does not look correct to me.
Again assuming this is the way the loads are being split up; I see needing one set of 5 50'
cables (1 each- 3 phases, neutral, and ground) with a pigtail at each end (10) to reach the
outside J Box splice point to connect to ATS-2. As it appears ATS-1 and ATS-3 will be just
over 100' from the generator, it will take 3 sets of 5 50' cables to get 150 amps to ATS-3
with another 10 pigtails, and 300 amps to ATS-1 will require the specified size 4/0 cables
to be paralleled, using up 6 sets of 5 50' cables and 20 pigtails. I come up with needing 50
cables and 40 pigtails. If you intended to run directly to ATS-2 instead of splicing, which
would make things easier, then you would need an additional 5 cables, so 55 cables and
still 40 pigtails.
Design Team Response: 4/0 Type W cable is rated 400A in free air. The intent is to run
temporary cabling exposed and not in conduit, but protected as necessary for construction
purposes. As such, 3 sets of cable are required per phase for 1200A rating. Also, the
number of cable sets called will allow a single set to be used for each of the three
temporary ATS feeders, per Phase 2, Drawing E-2.
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Brothers Electrical Corp., email from Michael Bavaro dated April 28, 2016
Summary of Question: Drawing C-2: Detail 3, Building 11 new transformer – Phase1
Layout; note #6: States excavate and install 3 new conduits. Please clarify who is
responsible for this excavation?
Design Team Response: The General Contractor is responsible for excavation and backfilling for
the new duct banks.
Griffin Electric, email from Michael Field dated May 2, 2016
Summary of Question: Is there a PCB Report on the 1500 KVA transformer being removed?
Design Team Response: No – there is no PCB Report for this transformer. The Electrical
Contractor shall assume that the oil contains PCBs.
Summary of Question: Is there a name plate on the 1500 KVA transformer being removed that
shows how many gallons of oil and weight of the transformer?
Design Team Response: We are not aware of a nameplate on the 1500 KVA transformer being
removed. The Electrical Contractor shall include in their estimate 450 gallons of oil that needs to
be disposed of. See updated Division III Specification Section 26000 (Electrical Systems) in
Addendum No. 2.
Brothers Electrical Corp., email from Michael Bavaro dated May 2, 2016
Summary of Question: Drawing E-1; One line riser indicates to replace the existing main
fuses with 1200amp fuses. Please indicate type of fuse to be provided.
Design Team Response: LPS-RK or LPN-RK type. See updated Division III Specification Section
26000 (Electrical Systems) in Addendum No. 2.
Summary of Question: Drawing C-4, detail #6 electrical duct bank indicates to provide
RGS conduit for underground trench. Please clarify / specify the different approved wiring
methods to be used:
Can PVC conduit be used underground for primary electrical service 13.8Kv
feeders?
Can PVC conduit be used underground for secondary feeders under 600V?
Can PVC conduit be used underground for the generator feeders and branch
circuit wiring? Please advise?
Design Team Response: All underground conduits shall be RGS encased in sand as shown on
Drawing C-4 and as shown in updated Division III Specification Section 26000 (Electrical
Systems) in Addendum No. 2.
Summary of Question: Drawing E-4: Please specify the approved wiring method for the
float switch & remote alarm panel wiring? PVC, EMT or Rigid Conduit?
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Design Team Response: All interior wiring shall be EMT. See updated Division III Specification
Section 26000 (Electrical Systems) in Addendum No. 2.
Summary of Question: Please provide approx. distance to carry, for the nearest 120v circuit
as indicated on drawing E-4 detail #8, float switch and remote alarm panel.
Design Team Response: Include costs for running 100 ft. of 120V circuit to an alarm panel.
Summary of Question: Please clarify / specify if the CAT6 cable as indicated on drawing E-
4 detail #8, float switch and remote alarm panel can be run exposed or will require a
conduit sleeve?…If it will require a conduit sleeve please indicate the approved wiring
method and approx. length required.
Design Team Response: Cat 6 can be run exposed above accessible ceilings. The detail
indicates to include 300’ of Cat 6 cable run. Include costs to run 150’ of EMT where
cabling cannot be run exposed. See updated Division III Specification Section 26000 (Electrical
Systems) in Addendum No. 2.
Summary of Question: Drawing E-1; Coded Note #13 states to connect the generator
annunciator to the building management system (BMS). Please provide the contact
information of current service contact vendor for the BMS.
Design Team Response: Automated Logic Corporation, Ludlow, MA Phone Number: (413) 5476595.
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