Questions and Answers to Project Documents — Business Opportunities
PROJECT:  Concourse B & C Sewer Repairs
NUMBER:  201950765-00

Current as of:  10/23/2019
 
Question Number  1:   Can the existing, cast in place sump pump lids remain in place in lieu of being replaced with drop in steel lids?
    Answer:   No - all steel lids to be provided
Question Number  2:   Will work be allowed to commence on concourse B and concourse C concurrently? Will this many sumps be allowed to be out of operation at the same time?
    Answer:   Contractor to coordinate with DEN. As long as there are adequate temporary pumps to bypass the individual sumps, then multiple sumps could be out of operation at once.
Question Number  3:   If we are limited by the number of pumps that can be shut down, the schedule will likely exceed the 365 day duration, what is the flexibility of this duration?
    Answer:   See item 2.
Question Number  4:   Are various motor centers in electrical rooms around the basement able to be shutdown temporarily and used for temporary power to bypass pumps?
    Answer:   Yes, alternate power sources are availabile. All shut downs need to be coordinated with DEN. This work most likely during off hours.
Question Number  5:   Is this project tax exempt?
    Answer:   The Contractor will submit a tax exemption form to the State to apply for tax exemption for this contract. If the application is accepted by the State, the contractor is exempt. The State Tax Exemption Request from DR0172 can be cound at the following website: https://www.colorado.gov/pacific/sites/default/files/DR0172.pdf
Question Number  6:   Can bypass pumps be tied into any existing electrical panels? What is the availability of space in electrical panels?
    Answer:   Contractor can tie in to existing electrical panels. Contractor to coordinate with DEN to identify panel location and availability. Anytime there is a tie in to an existing panel there will need to be a shut down request submitted to DEN. Panels should be shut down only during off shift hours.
Question Number  7:   Can doors/walls be removed/re-built to accommodate temporary equipment placing and install of pumps, lids, piping?
    Answer:   DEN will have to approve any temporary removal. Anything removed will be required to be put back in excellent working order, per standards, and code.
Question Number  8:   During the walk, it was mentioned that industrial sumps may contain glycol.  Is there an alternate procedure/product that is required for adhesion of liners in this situation?
    Answer:   Bid as the drawings indicated. If glycol is encountered in sumps during construction then an alternate solution may be considered at that time.
Question Number  9:   Do all sump pits have solid bottoms that will allow for attachment  of new equipment?
    Answer:   Refer to the instructions to bidders for unit pricing as designer was unable to see the bottom of the sumps during design.
Question Number  10:   Are seal-off electrical connections required (Accordance with article 504 of the national electric code) from the pumps to the controllers?
    Answer:   DEN Standard includes this safety feature. See Addendum 1
Question Number  11:   Do we need to salvage the existing rails?  If not, are there any procedures for removing overhead HVAC?
    Answer:   Anything removed will be required to be put back in excellent working order, per standards, and code. We would say salvaging existing rails is not required.
Question Number  12:   Are there any specific methods to identify seepage from ground water into sump pits?  Is GPR or Xray or other means needed, or is visual inspection acceptable?
    Answer:   Visual inspection will be acctepable.
Question Number  13:   Do the sump pit lids need to reflect exactly what is in the drawing details?
    Answer:   The best sump lids are built after all the items are in, then the Contractor would do an as-built to be exact. The drawings cover the scope and suggest layout. Contractor may need to adapt to the conditions in field.
Question Number  14:   Are there any fiber glass sump pits?  Would these require a different application of liner?
    Answer:   There are fiberglass sump pits. No requirement for a different liner.
Question Number  15:   Do the sump pits taper, or are they the same diameter at the top and the bottom?
    Answer:   Consistent diameter observed during design.
Question Number  16:   There are sump pit lids that are cast in the concrete slab floor of the mech rooms.  Are there any needed procedures for cutting and patching back the floor and reapplication of epoxy floor?
    Answer:   Follow the specification 017330 Cutting and Patching as required.
Question Number  17:   There are sump pits that are within a crawl space.  The vault door is smaller than the sump pit lid.  Can pit lids be multiple pieces?  The vent and discharge lines for these pumps are within CMU walls.  To what extent are these replaced?  Can these existing sump pump lids remain in place in lieu of replacing the lids
    Answer:   Refer to drawings.
Question Number  18:   Multiple sump pumps are tied into the BAS system.  What are the procedures and details for installing the controllers in these areas
    Answer:   The Sump Pumps on Concourse B are monitored by the BAS System and it could not be easier to tie to them. The controllers are in near proxiemty to all sumps on Concourse B. To clarify for Concourse C, install Annunciator Panel warning light system for (trouble codes) outside rooms with sump pumps.
Question Number  19:   What is the requirement for as-builts on the dye tests?
    Answer:   Record the source of the inflow.
Question Number  20:   Is CPVC being used, where are the transitions supposed to be?
    Answer:   Yes, refer to drawings.
Question Number  21:   Is there are requirement for Stainless Steel 304 vs 316?
    Answer:   No specific requirement.
Question Number  22:   What height are the annunciator panels to be mounted?
    Answer:   Mount at 80" AFF. Coordinate exact location with DEN.
Question Number  23:   The annunciator panels are to be silent with just an amber light?  While the controller is a red strobe with 85dB alarm?
    Answer:   Yes.
Question Number  24:   Sheet M101B – New construction note 11 – Are we installing remote alarms or are these by others? 
    Answer:   Remote alarms are to be installed as part of this project.
Question Number  25:   Is pipe material the same below the lid and above the lid or is CPVC being used in the sump pit?
    Answer:   Refer to drawings.
Question Number  26:   Will DEN provide the HSS security guards as needed? Or will these need to be paid for by the general contractor?
    Answer:   The allowance in the bid is to include the cost of security as part of the contract. Contractor to provide.
Question Number  27:   "Please clarify if sealoff fittings are required on any of the conduit coming out of the sump lids."
    Answer:   Although areas are not classified per code (for combustible materials), DEN is requiring sealoffs on all conduits coming out of sumps.
Question Number  28:   "On Concourse B it appears most of the existing controllers have a EMCS (BAS) Control cable. Can you provide additional details for what is being monitored, what kind of contact the existing system is utilizing and if any new programming would be required."
    Answer:   Details can be found on 1/M502 and 2/M502 both for Concourse B and Concourse C. “Contractor shall disconnect and reconnect existing monitoring at each location. Sump pump monitoring consists of a general alarm contact at each sump pump controller. When the alarm contact opens, an alarm is set at the EMCS. Type of contact is a SPDT relay, 24VAC, 10A with LED.”
Question Number  29:   "If temporary power would be required for a bypass pump, please clarify if it would need to be out of a different non-emergency power panel, with tie ins performed under an SDR on offshift hours."
    Answer:   Temporary power will be needed. Emergency/non-emergency panel will depend on location and availability of power. Refer to item 6 above. Coordinate with DEN.
Question Number  30:   "Please confirm the controller and annunciator are to be provided from the same manufacturer and the annunciator is fed from the controller. Both of these to be provided by the mechanical contractor."
    Answer:   Confirmed.
Question Number  31:   Please clarify what the control conduit & 11 # 14 conductors shown on Sheet E-501-B routed to the visual alarm are for, shouldn’t this be 120V wiring to power the visual alarm?
    Answer:   No, This is control wiring. Power is provided by control panel to annunciator panel.
Question Number  32:   " Flygt is listed as an acceptable manufacturer on the Effluent Pumps, but not the sewage pumps in section 221329. I would like permission to bid Flygt Pumps for section 221329 Part 2.1 - Submersible Sewage Pumps. The Flygt pumps we are proposing on are the same pumps that were approved for Concourse A Sewer Repairs."
    Answer:   Yes, Flygt is an acceptable alternate manufacturer for Submersible Sewage Pumps.
Question Number  33:   Suggested clarification from design team
    Answer:   Temporary pumps and hoses will be needed due to the time required for material curing during the sump lining process. The "containment vessel" shown in the drawings (3/M502) is to be used for the time needed to prepare for the installation of the bypass. Contractor to determine the means and methods to create the bypass.