American Samoa Power Authority

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2 American Samoa Power Authority P.O Box PPB Pago Pago, American Samoa Phone: (684) Facsimile: (684) In reply refer to: Purchase Two (2) Base load Diesel Generators RFP NO. 2009GEN 1011 June 19, 2009 This is to the Request for Proposals (RFP) for Purchase Two (2) Base load Diesel Generators, RFP NO. 2009GEN 1011, issued by the American Samoa Power Authority on May 6, responds to questions and issues received from prospective offerors after the issuance of Addendum 2 on June 1, IN REFERENCE TO THE RFP AND DIESEL GENERATORS: QUESTION 1: Page 3 of the RFP Can the period for binding be extended out longer? RESPONSE: Yes QUESTION 2: Page 3 of the RFP 180 days required for Open bids Are these exclusive days? Can we shorten it to 30 days? RESPONSE: It shall be changed to 100 calendar days, the evaluation and approval process takes time. QUESTION 3: How is the Clean Air Act handled per exemption? How do we guarantee final payment after Source Test? How does ASPA verify and Who pays? actually we can refine this as Does Subject to the U.S Clean Air Act mean EPA Tier Certified? The Generators are running Number #2 Bunk how does this interact with EPA or is this exempted? RESPONSE: American Samoa is a U.S Territory. US EPA Region IX standard federal permit conditions are applicable. At present operating with distillate # 2 Diesel (low sulfur diesel). This may change to Ultra low sulfur in the future. The new generator should be designed to run in both fuels. QUESTION 4: What are the circumstance Change Orders are allowed? What circumstance does Bidder pays for ASPA non compliance i.e. Authority equipment/parts non functional or manpower issues arise? In the event an unforeseen risk compromises completion of the job, who is at fault and what are the remedies? RESPONSE: Change Orders are typically not allowed; however, at ASPA s discretion and on a case by case basis, they may be considered. Issues for non compliance or unforeseen risk are generally too complex to be answered in the abstract. It would depend entirely upon details and circumstances of the particular situation. QUESTION 5: Page 19 of RFP? Can foundation be lengthen 4 6ʹ more for grating? Would ASPA accept a generator set with a greater than 4.75 MW rating? Question of the existing foundation may arise or inspection may not suffice. Have core samples of the last 6 months available? Or information available on the foundations condition? Page 2 of 7

3 3 RESPONSE: The foundation extension if needed would be a major undertaken offerer would need to consider time frame involved for such extension especially for Tafuna due to floor support, structure support and integrity of the overall floor. Offerer can submit proposal of how they plan to do this for Tafuna while for the Satala plant there is sufficient floor space to extend to the alternator side of the unit. Should it be needed? Either way justification for an extension should be supported accordingly especially when a fair cost is involved. ASPA will consider the rating up to 5.5 MW. Available data of the foundation in Tafuna is Class A concrete F c 3000 psi reinforced steel ASTM A615 Grade ton Deutz (Engine + Alternator) sits on the existing foundation that appears in good condition though we suggest the offerors should make final decision on the integrity of the foundation for their proposed unit. Existing foundation is slightly longer for it was designed for a V16 generator unit. Foundation plan with dimension is given in the attachment F rev1.0 for Tafuna. Attachment F2 identifies the T6 foundation as the proposed location for the new unit for the Tafuna plant with details of space available in the basement area for installation. In Satala, the offeror may design modifications to the existing foundation to accommodate the load requirement for the machine they are offering. The existing foundation was originally designated for a Nordberg unit in the early 70s and later transformed for an EMD skid mounted unit. Details from the old block reveal a 6.5ft foundation depth with reinforced rods for reinforcement. The existing proposed location holds an old EMD unit which is elevated 12 from the floor. If offeror desires, a new foundation may be constructed. Please see RFP item 5. and Attachment G Rev 1 and Attachment G1 which details the foundation length, building structure beams form and roof support height measurements from the floor QUESTION 6: Pages 6&10, Liquated Damages Fifteen Calendar months maybe insufficient to execute contract, is this negotiable? Can the liquidate damage requirement be met via rental generators? Can rental generators be furnished prior to the end of term to supply with unavailable generation capacity and energy? RESPONSE: Liquidated Damages are not negotiable. QUESTION 7: Is the final contract subject to American Samoa laws or can it adjust to states of service contract providers? RESPONSE: Yes, the final contract is subject to American Samoa laws. IN REFERENCE TO TAFUNA POWER PLANT: QUESTION 1: Are there any cable layout plans for the power station? RESPONSE: Please see Tafuna Plant photos ( Attachment 1 ) for information on this. All cabling run on trays 6.5ft above floor level. Should more trays be required then offeror must consider adequate spacing to allow freedom of movement for maintenance and service in the area. Space is available for additional cable trays of up to 2ft wide. QUESTION 2: Can you advise full details of the existing station control system? RESPONSE: Control room, is simply for monitoring purposes, as it is, SCADA information is available with the use of the FIX Intellution software package employing an Allen Bradley PLC5 unit. The same system includes Water and Waste Water controls and monitoring although a different data control module is used for both water and waste water systems. The electric side of the operation collects data from power monitors (daisy chain) to a Co processor card on Modbus protocol. Feeder information is also included. (See also Question 3, response). The controllers on the existing generator units is about 20 years old and are not interconnected (NO CAN Bus and the likes). The generator units operate individually and are all manually started by operator pressing a button. The units are controlled individually with operators monitoring and adjusting load and vars as necessary Clocks and the frequency is used for demand matching. Page 3 of 7

4 4 480 volt 3phase 60 Hz supply is used for the station services supply source, although there is 208/120 available, for light loads. QUESTION 3: What is the expectation of the new GenSet to link into the station control system? Can you advise details? RESPONSE: s/w gear and associated controls of T6 can be used for the new generator with required changes in the ratings. 480V supply source for the new unit MCC and local control panel for the generator. Further, The existing SCADA set up only monitors the load and confined only to parameters available on a power meter unit etc, however we would like to move to the next level and include the controls, start, stop, load controls, var controls tracking of engine and generator parameters all from the PC. We would recommend that the offeror add on to our existing setup and modify the program accordingly to accommodate the additional unit tags. (Once the bid has been awarded, we will give the winning offeror a copy of the complete Allen Bradley program and the Intellution Data base for modifications to accommodate the new generators). Should the offeror prefer to provide their own system then provisions must be made available on the provided system for the existing ASPA generator units for future extension. We will weigh the advantages of both options and decide accordingly. We prefer however to hold on the existing hardware (PLC etc) unless an exchange or trade in can be arranged. ASPA operates a WAN Ethernet system over a fiber optic link between the two power plants. Electrically the two plants (Tafuna and Satala) are tied with a 5MVA transmission line (34.5kV). About 500 points are available with the FIX Intellution package for additional control tags. QUESTION 4: Can you advise what is the full area available (at the radiator end) in the basement for auxiliary RESPONSE: Please see attachments F1 and F2. Auxiliary equipment showing in the basement around the T6 foundation block will be cleared for new generator installation. Available space = 14 x x 10. QUESTION 5: Can you advise what is the full area available (at the radiator end) on the ground floor for auxiliary RESPONSE: Area within secondary containment for radiators and pumps if need be: 320 x 708. Please also see Attachment F rev.1.0 and Attachment T01/02. IN REFERENCE TO SATALA POWER PLANT: QUESTION 6: Are there any cable layout plans for the power station? RESPONSE: All the engines cabling in Satala run through a cable trench which covers the length of the plant terminating at the switch gear end. Each existing generator taps to this trench with a smaller trench which runs on either side of the generators or by conduits embedded in concrete. The offeror based upon the connection requirements and the number of cable to run may choose either or both as tapping media to the existing station trench. There is room for the new generator cabling and additional should it be needed. Please also see Attachment G1 for details. Cabling to external devices what ever they may be would run underneath the floor which is open only from the end of the engine block side to the wall facing the radiators. These may need to run through conduits to provide the isolation from oil etc. A trench is also available outside which runs from the switchgear room to all the radiators as an alternative route for cabling radiator fans. QUESTION 7: Can you advise full details of the existing station control system? RESPONSE: 480volt 3phase 60 Hz supply is used for local control panels. The switchgear and control system is a prefabricated unit with the switchgear at the ground floor and control room on top. All synchronizing and load control is done from the control room which also houses all the manual and automatic excitation equipment. Page 4 of 7

5 Page 5 of 7 5 The system as it is operates manually by means of operator control although there is SCADA capabilities. Where and Allen Bradley PLC 5 is used for data collection and IO interfacing Fix Intellution is the SCADA package. In fact the two plants Satala operate the same package and same data base with the either side operating as back up for the other, information is shared between the two where the stored data base on either side is updated as new information becomes available from the field stations. Again it s only monitoring on the power generation side while water and waste water operates controls as well. Current operation: Each generator is started at the engine control panel, and taken to rated speed; once all is clear for load the operator moves to the control room where synchronizing takes place, from there the unit can be raised and lowered for loading and unloading, emergency stop is available from the control to shutdown unit and trip/open the circuit breaker. Remote start on the generators had never been looked at however additional equipment is needed to facilitate this feature on the generator control and annunciation equipment and control system. QUESTION 8: What is the expectation of the new GenSet to link into the station control system? Can you advise details? RESPONSE: Provisions are there in the existing Main bus with MV S/W gear. Source of the 480 Volt side spare spaces are available in the Siemens indoor type R metal clad s/w panel to insert new circuit breaker. Siemens indoor type R metal clad, RLF800 EO/MO 800AS TS1 TZ. Circuit breaker is required for 480V supply to connect new LCP. Furthermore, we would like to keep the existing excitation system in place considering the control room has all the connection and wiring in place. However the offeror may with adequate reasoning recommend one that would match the new generator s control system requirements, while at the same time not interfere with the wiring of the currently operating system. A sequence of event logger is in use at the control room which will take in inputs from the engine (common) alarms signal (NO potential free contact) to signify an event. Two (2) inputs are available from the engine parameter ( LCP ) for this purpose while a number of inputs relating to the designated CB and Protection Relay status have been prewired for event logging. The existing set up we have only monitors the load etc, however we would like to move forward and include the controls, start, stop, load controls, var controls tracking of engine and alternator parameters from the PC, as the remote point.. We would recommend that the offeror add on to our existing setup and modify the program accordingly to accommodate for the new machine. (Once the RFP has been awarded, we will give the winning offeror a copy of the complete Allen Bradley program and the Intellution Data base for modifications to accommodate the new generators). Should the offeror prefer their own system then provisions must be available on the new system to extend to existing generator units which may be later connected to the new system. Of course we will weigh the advantages of both systems and decide accordingly. What ever we decide on at the end would be based heavily on whether it includes the equipment we already have. (Fix Intellution and hardware, PLC etc ) It is important also to note the Satala Plant has a built in excitation system. What we mean by this is that there is already a Basler Excitation system in the control set up of the plant to accommodate for the 9 units that can be operated at the plant. All uses the SSR6312 Basler AVR. The system includes VAr and PF controls and a back up manual excitation module. Should the Offeror find the available system incompatible with the machine they wish to offer for Satala (only) then any new equipment must be suitable for mounting inside the existing excitation cubicles. Please see also RFP Attachment C item 13.c and the Single line diagram of the plant Attachment E QUESTION 9: Can you advise the space between the upright beams on the radiator wall? RESPONSE: 21ft.

6 6 QUESTION 10: Can we assume the wall is all 8 concrete block? RESPONSE: Yes QUESTION 11: Can the roof be removed for access for the new GenSet? RESPONSE: It is possible. Photos of the Satala plant inside view (Attachment S01) shows the roof support structure. Please see also the attachment G Rev 1.0 for details. Further more care must be taken with re instating the layers (roof is stainless steel clued between sheets and screwed to the structure purlins). QUESTION 12: Can you advise the height where the support beam meets the roof truss? (Inside measurement) RESPONSE: 14 ft. Please see also Attachment G rev 1.0 for more details. QUESTION 13: Can the roof line be changed if required around the area for the new GenSet? RESPONSE: A considerable amount work would be required including raising the crane beams. Perhaps lowering the foundation to accommodate the engine height would be an alternative. It s the integrity of the roof to withstand the design wind speeds that worries us, raising a portion of the roof would exposed the vulnerable structure to the elements. However having said that, the Offeror may propose a design plan with the estimated costs involved should this be necessary. We can accept a temporary raise just top move the unit in position but a permanent installation would be questionable. QUESTION 14: Are there any roof height limitations? RESPONSE: There are other structures mounted to the frame and building truss, which includes the extractor blowers. See also concerns in reply to Question 8. QUESTION 15: Can you advise the S9 EMD foundation size? (Including existing depth?) RESPONSE: Foundation length 34ft 5 ½ inch x width 12ft. and height 11 ½ inch above the ground level. Depth is 6.5ft. (That s the available information.) Please see also response to question 5. QUESTION 16: You state the floor loading to be 10 ton. Is that per square foot? RESPONSE: Not precisely, but 90 ton Deutz engine moved through this floor. We have move through almost the length of the plant (Satala the complete unit with alternator) however support was provided to widen the effective load area where the rollers were positioned. We can assume a 5ton per square ft to be safe. On both plant floors except for Tafuna basement ceiling/floor where it is supported in part by concrete columns and support beams. QUESTION 17: Can you advise the distance between the radiator wall and the existing S9 base? We assume that the current foundation is 32.5 in total length? RESPONSE: 80ft and yes QUESTION 18: Can you advise measurement from S9 base to back wall? RESPONSE: 23ft. QUESTION 19: Are there any limitations for the height of the exhaust system? RESPONSE: No, however the design wind speed of the plants is about 200mil/hr for Satala and less for Tafuna plants so support and anchors would need to consider these limits. QUESTION 20: Can you advise what is the full area available (at the radiator end) on the ground floor for auxiliary RESPONSE: See the photos of Satala plants outside & inside (Attachment S01 / S02). Page 6 of 7

7 7 QUESTION 21: Can you advise what is the full area available (at the back wall end) on the ground floor for auxiliary RESPONSE: Auxiliary equipments against the wall from the location of the new engine will be removed prior to installation. Estimated available space inside: 15Ft x 15ft x 13ft (height), while outdoor would be about 30ft long by 19ft wide. An access maintenance opening exists between the radiators and the plant this is about 20ft to the power plant wall. This is mainly used by vehicle for maintenance services. QUESTION 22: Can you advise if it is possible to locate some equipment if needed outside on the back wall using a raised platform? RESPONSE: It depends on the type and size of equipment used. However the limitations are weather and the environment, then there is the existing intake sound barrier baffles installation which takes a fair bit of space. These extend to about 8ft outside the plant and rise to about 12ft above plant floor level. Offeror must take this into consideration when proposing outdoor mounted equipment. See attachment photo of Satala plant and Ariel shots Attachment S01 / S02.. # # # # END OF ADDENDUM 3 # # # # Page 7 of 7