Questions and Answers to Project Documents — Business Opportunities
PROJECT:  Boiler 1, 3, 4, and Hydronic Pump Replacement
NUMBER:  201951349-00

Current as of:  7/4/2020
Question Number  1:   Per Page 6 of the Project Requirements for the Subject Project, Checklist: Required Proposal Forms, it is written that we must provide the following, however these documents were not provided with the proposal. Can DEN please provide? Federal forms: o Certificate of Buy American Compliance for Total Facility, o Certificate of Buy American Compliance for Manufactured Products
    Answer:   The inclusion of the Federal forms requested at the bottom of Page 6 was an oversight; those two forms are not applicable to this project. Page 6 will be revised with Addendum 1 to remove the two listed forms are being required for this procurement.
Question Number  2:   Specification 230900 2.2.D - Items 1 thru 4 call out for DDC control system is to include the various items listed in this section. Confirm that these systems are excluded and provided by others.
    Answer:   Confirmed these systems are existing and shall be coordinated with new work.
Question Number  3:   Specification 230923 2.1.A.1 - Confirm that the new DDC system shall interface into both the existing CUP Johnson Controls Metasys system and the airport Honeywell EBI system. Airport facility operators shall be able to use systems to monitor and control connected equipment. Controls contractor to perform all the software and hardware work necessary with these existing systems to accomplish the design.
    Answer:   The intent is for new controls (namely in the pump rooms) to utilize existing network drops and shall be integrated with the JCI control system.
Question Number  4:   Specification 230923.1.11 - Confirm that the EMCS and DDC system warranty period is two years.
    Answer:   Per spec. 262713, EMCS Technical support is two years beginning with Substantial Completion. Per spec. 230923 Product parts inventory to support on-going DDC system operation for a period not less than 5 years after Substantial Completion.
Question Number  5:   Specification 230923.3.22.B - In order to properly price the work, specify the amount of customer training hours for various types of training listed.
    Answer:   The requirement is a minimum of eight (8) hours of operator training per shift per course and on site.
Question Number  6:   Specification 230923.23 - Confirm that the use of Setra Model 230 (2.2, D) is acceptable for application listed in paragraph 3.2, B. Liquid-Pressure Differential Transmitter. These sensors match the DP transmitters used on the previous boiler replacement project.
    Answer:   Per the specification this is acceptable.
Question Number  7:   Specification 230923.23 - Confirm that it is acceptable to substitute Kele PTX1 Series pressure transmitters for liquid gage pressure measurement (catalog sheet attached)? Model PTX1E matches the gage pressure sensors used on the previous boiler replacement project.
    Answer:   Once under contract, specification 012510 must be followed to request substitutions.
Question Number  8:   Drawing M 4.14 - Which trade is responsible for furnishing boiler NG mass flow meters (shown on natural gas P&ID, M4.14)?
    Answer:   Scope assignment is the responsibility of the general contractor.
Question Number  9:   Drawing M 6.03 - Which trade is responsible for furnishing boiler fuel oil flow meters (not shown on any P&ID, but indicated to monitor on point list M6.03)?
    Answer:   Scope assignment is the responsibility of the general contractor.
Question Number  10:   Drawing M 4.16 - Confirm boiler flue dampers and actuators are furnished by boiler manufacturer (see Note 2, Sheet M4.16)? It is shown within the dashed line implying it is part of the boiler manufacturers package.
    Answer:   The flue damper is included in the boiler specification as a shipped loose item and will be controlled by the boiler controller therefore coordination is required to assign installation, power, and wiring scope.
Question Number  11:   Drawing M 4.16 - Are header pressure sensors shown on M4.16 (PIT-500, PIT-501, PIT-504, & PIT-512) existing or do they need to be added under this project?
    Answer:   Refer to M4.11 and M4.12 for new/existing instrumentation.
Question Number  12:   Drawings M 6.01/M 6.03 - Control valves TCV-13,14,15 are shown on the schedule (M6.01) with modulating 4-20mA actuators, but the point list (M6.03) shows a digital output for open/close. Are the valves to be modulating or two-position?
    Answer:   The intent is for valves to be modulating.
Question Number  13:   Drawings M 6.01/M 6.03 - TML and AOB Pump Rooms: Control valves TCV-003,004,005,006 are shown on the schedule (M6.01) with modulating 2-10VDC actuators, but the point list (M6.03) shows a digital output for open/close. Are the valves to be modulating or two-position?
    Answer:   The intent is for valves to be modulating.
Question Number  14:   Drawings M 6.01/M 6.02 - CCA, CCB & CCC Pump Rooms: Control valves TCV-003,004 are shown on the schedule (M6.01) with modulating 2-10VDC actuators, but the point list (M6.02) shows a digital output for open/close. Are the valves to be modulating or two-position?
    Answer:   The intent is for valves to be modulating.
Question Number  15:   Drawing M 6.01 - CCA, CCB & CCC Pump Rooms: Schedule (M6.01) lists a control valve TCV-005 serving a ‘CCx FCU’, but there is no direction for how to control this new valve serving the existing FCU. Please provide sequence of operation for this valve and if there are any other points of control to be provided for the existing FCU.
    Answer:   Match the control intent for TML/AOB Volume 2 approach for FCU control.
Question Number  16:   Drawing M 6.01 - CCB Pump Room: CW & HW Pump Room P&ID (M4.41) for CCB differs from CCA and CCC pump rooms. CCA and CCC have pressure and temperature sensors entering and leaving the pump room on the plant side of the room. CCB does not show the same sensors. Is this intentional or should CCB pump room also have these sensors?
    Answer:   Confirmed the intent was for CCB not to have additional sensors. The additional sensors were added to capture the temperatures upstream of the PCA plant rooms which are specific to CCA and CCC.
Question Number  17:   Specification 230923 2.4 - Confirm that the existing CUP UPS power will be provided for control equipment and panel UPS's are not required.
    Answer:   Local panel UPSs are not required.
Question Number  18:   Specification 230923 2.5.A - Confirm that controller display can be used to monitor, control, and override equipment and that panel mounted switches are not required.
    Answer:   Confirmed panel mounted switches are not required.
Question Number  19:   (Concrete) Please provide the infill opening detail described in Keynote 16 on Sheet S1.40. Detail 3/S5.35 does not pertain to infill openings.
    Answer:   See Volume 3 detail 7 on sheet S5.35.
Question Number  20:   Please confirm the existing crane will be able to lift the new boilers.
    Answer:   Current boiler replacements, 5A and 5B, weighing 24,000 lbs. each used the existing hoist way and crane. Contractor to confirm crane capacity and rigging needs for their scope of work.
Question Number  21:   Please clarify the maximum allowable height of cranes on the airfield on Taxiway AA in front of the CUP. Is there a standing 7460 form in place?
    Answer:   There is a main campus 7460 permit available with a maximum crane height of 100ft. This will require a Taxiway AA shutdown. All crane plans are to be submitted for preapproval.
Question Number  22:   Can you please provide an “equipment install/removal route” similar to the one shown on Sheet M1.11 for the equipment shown on Sheet M1.16?
    Answer:   Please see the exhibit entitled “DEN CUP ADS ACCESS” sheets SK-1 and SK-2, which shows recommended ADS equipment access into the CUP. This can be found as “Miscellaneous 1” on the project page at Equipment modifications are acceptable to minimize existing site constraints and must be submitted in advance for DEN review.
Question Number  23:   Are hot tap stop-o's acceptable for various applications throughout the project?
    Answer:   DEN does not allow hot taps in typical fabrication; however, in outstanding circumstances, the Contractor may submit an exemption request for DEN review.
Question Number  24:   Are pipe sleeve reinforcements acceptable for tie-ins on existing pipe with degradation?
    Answer:   Instances of pipe degradation should not be assumed. If found, submit RFI to DEN for evaluation and process forward.
Question Number  25:   At what locations are temporary pumps required?
    Answer:   During the off-peak period, temporary pumping will be required to maintain 24/7 operation of systems while work is performed. Designer recommends two (2) 20hp, temporary, chilled water pumps be estimated for each concourse pump room for a duration of 6 months during seasons of lower load demands (winter). The intent is to coordinate seasonal outages for the heating water system.
Question Number  26:   Where is temporary cooling required?
    Answer:   Temporary cooling requirements are dictated by coordinated outages. Refer to specification 011400, Appendix A. Outages not identified in Appendix A, will be evaluated on a case-by-case basis.
Question Number  27:   What are the pre-qualifications or requirements for a mechanical contractor priming this project?
    Answer:   Prequalification category 2F Mechanical is required at the $18,000,000 level in accordance with the City’s Rules and Regulations Governing Prequalification of Contractors.
Question Number  28:   Volume 1 – Drawing S5.04 Detail 1 shows supporting exterior flues but does not show the band lateral brace or plate wall support member sizes and connection details. Please provide details for steel support sizes and connection details to building.
    Answer:   Please refer to the notes on the referenced sheet. As part of the flue system, the Contractor must provide design of the supports of this system. The supports designed must be compatible with the flue diameter, flanges, etc. The support types and locations depicted on the schematic detail are not intended to represent final installed conditions.
Question Number  29:   Please confirm if the “Manual Trolley’s” shown in pump rooms are to be included in the project cost or if they are indeed “By Others” and not a part of the project cost?
    Answer:   Manual Trolleys are intended to be provided by DEN and should not be included in pricing.
Question Number  30:   Please confirm where anchoring into CMU block per Volume 2 – Drawing S5.22 detail 2, that these CMU cells are solid grout filled blocks. Also, at any other CMU anchoring where epoxy or expansion anchors are used that these cells are solid grout filled.
    Answer:   Which individual CMU cells are grouted cannot be confirmed without extensive field testing; therefore, the Contractor is required to GPR at all anchor locations. For anchor selection and installation, it should be assumed that CMU cells are un-grouted unless field-verified to be otherwise.
Question Number  31:   Please confirm that GPR is required at all structural anchor points to existing concrete and CMU as well as at all areas where core drilling or saw cutting shall occur.
    Answer:   See previous answer.
Question Number  32:   Please confirm that in the CUP area, only the use of electrical forklifts and man lifts is allowed.
    Answer:   Yes, both forklifts and man lifts are allowed in the Central Utility Plant, but all must conform to DEN Rules and Regulations. See response to the next question below.
Question Number  33:   Please confirm that in the tunnels and pump rooms, only the use of electrical or natural gas equipment is allowed.
    Answer:   Per DEN Rules & Regulations; 130.04 Vehicle Traffic in Service Tunnels and Baggage Areas 130.04-1 All vehicles operating in the service tunnels, baggage makeup areas, or other enclosed areas at the Airport must be electric (battery) powered or operated on Compressed Natural Gas (CNG). Receipt of an Airport Vehicle Permit for a CNG vehicle may be conditioned upon passing an annual emissions test conducted by the City or its authorized agents. The City shall publish permitted levels of emission and monitor compliance for vehicles operating within the enclosed area. Vehicles equipped with duel fuel systems (e.g. gasoline/electric hybrids, gasoline/CNG) are not permitted access to the service tunnels.
Question Number  34:   Do the landings need to be painted? Details 7/S5.21, 7/S5.31, 7/S5.41, 7/S5.51 do not show paint being required.
    Answer:   The intent is to have all landings and raised curbs to be painted per DEN standard.
Question Number  35:   Is Door 001 in Pump Room TML_04_5E_144 to be new as outlined on Sheet A1.20 or moved from the existing location as outlined on Sheet S1.20?
    Answer:   The intent is for a new door to be provided per sheet A1.20.
Question Number  36:   Is there to be a drywall patch of the existing wall once the fan is removed as shown on Sheet MD5.02?
    Answer:   The intent is for a patch to be provided to match existing wall.
Question Number  37:   Regarding air/dirt separators CUP ADS 1, 2, they indicate flow of 14,400 with future flow of 20,870. These are too high for this size unit, confirm actual flow requirement and ADS size. Please clarify.
    Answer:   The intent is for each new CHW CUP ADS is to have a max design flow rate of 12,500 GPM, which accommodates future Chilled Water flow requirements.
Question Number  38:   Regarding air/dirt separators AOB-ADS-1, during design it was indicated this unit needed to be less than 90” tall due to ceiling and drainage clearances, is this no longer the case?
    Answer:   There is approximately 117” total available height at the location of this ADS. This height shall accommodate the vessel, air-vent above, and drain assembly below
Question Number  39:   From the boiler specification section: Warranty Period for Drums, Tubes, Headers, Cabinets, and Atmospheric Gas Burner: Minimum five (5) years from date of Substantial Completion, pro rata. Please confirm what is meant by pro-rated?
    Answer:   The term “pro rata” is a warranty term speaking to the ratio remaining in warranty to remaining component value.
Question Number  40:   Regarding the pumps: Schedule notes indicate “selection information is for the BEP Point of Basis Pump, also select pump based on […]” Do pumps need to operate at duty point indicated on schedules, or only at design condition cases listed in notes?
    Answer:   The intent is for pumps to be selected considering the scheduled BEP point, however pump selections should also consider BEP for the alternate points.
Question Number  41:   Regarding the pumps: Is there a maximum head the pumps can develop i.e. dead head.?
    Answer:   Pumps shall be limited to 180 FT max pressure (i.e. dead head) to remain under the existing system pressure thresholds.
Question Number  42:   Is the terminal bridge rail to be removed? What about shoring for the bridge for pump transport? What about louver removal or cutout in the deck wall?
    Answer:   The design intent is to remove a section of rail to be replaced with a removable rail. Shoring for assumed pathway into the pump room is dictated by the Contractor’s means and methods. Refer to SD1.20 for temporary loading notes. Alternate pathways into the room are the responsibility of the installing Contractor.
Question Number  43:   What are the weld testing requirements? Are 10%, 50% or 100% inspections required? Are X-rays required?
    Answer:   Refer to specification 050510 and 230500 section 3.6 for welding requirements with the most current reference standards. Typical Contractor’s Quality Control testing includes 100% visual inspection and 10% magnetic particle inspection, and once under contract, will need to be reviewed by DEN.
Question Number  44:   May hangers/supports for existing blowdown piping to be replaced, be reused/utilized for new blowdown piping?
    Answer:   The intent is to replace hangers with stainless steel and new stainless-steel anchors into crawlspace ceiling.
Question Number  45:   May glycol be stored in totes in boiler room or does it need to be relocated and stored offsite?
    Answer:   Only when applicable to scope, Glycol is to be stored offsite per DEN Life Safety.
Question Number  46:   Please confirm dimensions of crawl space. Is this a confined space? What is the access size and locations?
    Answer:   The Central Utility Plant crawl space is considered a confined space. Refer to sheets MD1.11 and MD1.12. There are two entrances approximately 4’ x 4’ in size. One is located on the East side in the areaway near column E6/N1 and the other on the West side near the CHW air-dirt-separators near column W6/S3.
Question Number  47:   Please confirm the dimensions of the void space a grade where boiler flues transition outside. Is this a confined space? What is the access size and location(s)?
    Answer:   This is not a confined space, the depth of the space is 4 ft., and the locations are the cooling tower level from above, the north Mezzanine, and the boiler room from below.
Question Number  48:   Relief valves are shown on the boiler inlet. Please confirm if relief valves are required on the inlet/outlet side, or both.
    Answer:   Safety reliefs are intended to be provided with the boiler per specifications.
Question Number  49:   Some of the pipe flow directional arrows appear to be facing the wrong direction. Please clarify.
    Answer:   Please clarify locations. Flow directional arrows can be coordinated with selected bidder prior to construction activities.
Question Number  50:   What is the basis-of-design boiler? Is there a cut/spec sheet available?
    Answer:   Specifications indicate acceptable boiler manufacturers and drawings indicate performance requirements. Refer to specification 016000 section 2.2.
Question Number  51:   Who is responsible for redesign and coordination of piping/flues/connections if basis-of-design boilers are not carried in bid? Is any redesign that would need to occur be required to be completed by Burns and McDonnell?
    Answer:   All design related questions are to be presented to DEN through the formal RFI process. Any required changes will be made per the 2011 Edition of the City’s Standards Specifications for Construction General Contract Conditions and the contract itself.
Question Number  52:   Can the crane for the pump rooms be set on the road? Next to building? Please provide locations where crane may or may not be set.
    Answer:   Crane use for the pump room scope is not applicable. Use of natural gas or electric vehicles is allowed.
Question Number  53:   Does pipe insulation jacketing need to be painted?
    Answer:   For hydronic piping, the intent is the use of colored PVC jacketing per specification 230719. Refer to Division 09 for painting requirements for non-PVC jacketed pipe and uninsulated pipe.
Question Number  54:   We request that the bid date of 10-14 be extended in order to prepare our responses once we receive answers to the clarifications and questions.
    Answer:   We plan on extending the due date for submittals with Addendum 1, which we anticipate posting by the end of the day on October 11, 2019. Addendum 1 will be found on the project page for this opportunity: