Atch_8_-_Q&A_Responses.pdf

No. Question Response

Please provide a controls narrative for the ash handling controls system. Appendix A-C attached - Appendix A is Sequence of Operation. Attach Appendix A-C to the end of specification 40 95 00

2 Please provide any additional P&IDs regarding the ash system and controls system. P&ID of system are drawings 46 through 48 of drawing set

Please provide Human Machine Interface (HMI) documentation for the ash controls system. Contractor to provide HMI layout and documentation for complete and operational system as indicated in specification 40 95

00 2.3. The existing HMI graphics are acceptable level of detail. Additional information in Appendix A for HMI screen content.

4 Bid documents reference an I/O list. Please provide an I/O list for the controls system. Appendix A-C attached - Appendix B is I/O list indicated

Please provide the existing program file for the controls system. Most of the existing programs is available from EAFB power plant after award. They are machine language files of various systems. They were useful for details that are indicated in the design documents.

Section 01 14 00 1.1 a. (4) mentions fly ash unloading controls and references the use of a bypass for the fly ash and a slide gate installation. Please confirm the bypass method is an existing system currently in place for use as described or if the contractor is responsible for providing a bypass system. We cannot find anywhere else in the contract documents or drawings a reference to a slide gate installation or details on how to install it including what to provide.

The bypass currently exists and may be utilized by the Contractor per the allowances in 01 14 00. The slide gate was initially considered for replacement but removed from the scope of work during design. Revise 01 14 00 Para 1.1.a(3) third sentence to read, "The fly ash silo can be down for 4 days for control replacement".

Please confirm there is a requirement to install a slide gate and if so please provide drawing details on how to accomplish it. Alternatively if it is not a new installation please confirm it is part of an existing ash bypass system to be utilized as described during the fly ash silo shutdowns.

Revise 01 14 00 Para 1.1.a(3) third sentence to read, "The fly ash silo can be down for 4 days for control replacement". The slide gate was initially considered for replacement but removed from the scope of work during design.

Drawing IP300 indicates two new level transmitters to be installed. The only detail provided for these instruments is on page II001 and does not specify a desired make/model for level transmitter.

Additionally there are no specific details for the level transmitters in the project specifications.

Could the two level transmitters be further clarified.

Appendix A-C attached. Appendix C is instrument data sheets for the level transmitters. Rosemount Level transmitter is basis of design. See attached cut sheet

A pre-existing flange was pointed out on top of the bottom ash silo during the job walk. Please confirm that this flange is to be used for mounting the level transmitter.

The flange may be used for level transmitter installation. Contractor may be required to modify the flange to allow transmitter to provide accurate level readings to bottom of cone. Level measurement shall be demonstrated over entire volume of silo. See detail II001. Plan location indicated on IP300

The fly ash silo does not have a preexisting flange or any other attachment points, would it be acceptable to weld a flange on top of the fly ash silo as a mounting point for the level transmitter.

Provide a flange similar to the other silo and as indicated in II001 for the level sensor. Level measurement shall be demonstrated over entire volume of silo. See detail II001. Manual gauging level station shall remain. Plan location indicated on IP300

11 What are the fire protection requirements for welding a flange on top of the fly ash silo? Para 3.5 has been added to 01 73 29 Cutting and Patching. Please see revised specification attached

Note 1 on drawing IP300, comments that a kick plate is to be used for instrument protection; can this kick plate be omitted? The flange connection elevates the instrument above the walking surface and the kick plate will serve no purpose.

Provide kick plate at needed to protect cabling and junction box connections as needed.

Are these new PLCs or replacements? Are they tied in via Ethernet to the rest of the system?

(Control System Architecture indicates they are not.)

These are New PLC and HMI. They are not tied to the rest of the system as indicated.

a. Bottom Ash Unloading PLC – need existing program Existing PLC program is available from plant on award. New PLC program shall be developed by contractor to meet the sequence of operation and I/O indicated in Attachment A-C attached drawing package

b. Fly Ash Wet Unloading Station PLC – need existing program Existing PLC program is available from plant on award. New PLC program shall be developed by contractor to meet the sequence of operation and I/O indicated in Attachment A-C attached drawing package

c. Pulse Air Panel Bag Filter #1 PLC – need existing program Existing PLC program is available from plant on award. New PLC program shall be developed by contractor to meet the sequence of operation and I/O indicated in Attachment A-C attached drawing package

d. Pulse Air Panel Bag Filter #2 PLC – need existing program Existing PLC program is available from plant on award. New PLC program shall be developed by contractor to meet the sequence of operation and I/O indicated in Attachment A-C attached drawing package

May we have copies of the PLC and HMI application files – If we cannot get these, please send screen shots of all HMI screens and/or the graphics panel and a print out of all PLC programs if available.

Existing PLC program is available from plant on award. New PLC program shall be developed by contractor to meet the sequence of operation and I/O indicated in Attachment A-C attached drawing package

a. Fly Ash Panel PLC – need existing program Existing PLC program is available from plant on award. New PLC program shall be developed by contractor to meet the sequence of operation and I/O indicated in Attachment A-C attached drawing package

Ash Handling Bid Questions

Per bid walk, Owner is to blow accumulated dust off all existing equipment to be demolished. Please confirm

Precleaning is the responsibility of the contractor. Refer to hazardous materials report for information regarding ACM and

Silica in dust. Precleaning shall be performed by qualified workers utilizing proper PPE and disposal requirements. Add the following to 02 41 para 1.2.1, "Precleaning of equipment for demolition is the responsibility of the Contractor and shall be done utilizing qualified personnel and required disposal techniques. The Contractor's approach to precleaning shall be described in the Demolition/Deconstruction Plan". Add the following to 01 50 00 para 3.6, "The Contractor is responsible to protect the work environment from dust that occurs as part of plant operations. The Contractor is responsible to remove dust accumulation from the work area that may result from plant operations that occur in the evenings or on weekends when the work area is closed down."

No scope narrative, specifications, or installation details regarding the compressed air system were provided in the RFP. Please provide.

Provide compressed air to cool cabinets in accordance with drawing PI300. Add to specification 40 95 00 2.4.1 " Provide

Vortex Cooler for cabinet cooling. Utilize plant compressed air through vortex device to provide subcooled air to cabinet for pressurization and cooling. 8-35 CFM depending on cabinet cooling load.

Do compressed air lines outside of the boiler house need to be insulated? Contractor provided compressed air system connects to the plant air system within existing heated buildings. Pipe insulation is not required

Drawing IA260 shows 4 EA. Unloading Station Level Detection Panels. The corresponding P&ID IS260 shows each panel requires compressed air and has a 3/8” probe hose. Where are these panels located? Drawing IS260 states they are in the unloading area. Is there an install detail for the probe?

Level probe are indicated in ASH silo level of drawing IP210. Probes are to ride unloading spouts similar to existing installations on the spouts. See Page 13 of 19 off attached design analysis for reference for picture of existing tubing on unloading spout. Existing unloading spout is an Midwest International Paragon loader.

When installing the new BA & FA PLC are we to install new conductors to all the existing field devices/instruments? Drawing IA100

Wiring is to be modified only as required to swing to new cabinets. Field wiring from cabinet to devices is not intended for replacement. All work should occur at cabinet only, and limited few field devices (eg. silo indicators)

When relocating the existing conduit from the side to the top of FA1, if the existing conductors are too short can we extend the cables using terminal blocks? Drawing IA100

Yes. Cables may be extended using a terminal block if desired by contractor

21 What make and style is existing panel LP-1? Drawing E101 Existing Panel LP-1 is a GE A-Series Panel.

22 What type of enclosure is required for new panel LP-2? Drawing E-103 New Panel LP-2 should be provided with a NEMA 12 enclosure.

Regarding Solicitation FA500419BA015 Ash Handling Control System at CHPP, will electronic submittal of proposals be acceptable? Form 1442 Item 13 states offers are due at place specified in

Item 8. However, no location is specified in Item 8.

Electronic Bids will not be accepted. Bids must be sent to the following:

FA5004 354 CONS PK

CP 907 377 5207

2310 CENTRAL AVE STE 3

EIELSON AFB AK 99702-2200

United States

25 Are we providing field devices such as Valves, Sensors & Transducers, etc..? Yes.

26 Are we Programming the newly installed PLC? Yes.