COPY APPENDIX APROJECT DESCRIPTION AND DESIGN CONDITIONS

TABLE OF CONTENTSPART A OPEN CYCLE PLANT, COMBINED CYCLE PLANT AND COMPLETED SPECIAL FACILITIES I. GENERAL II. DEFINITIONSIII. MECHANICAL PLANT

A. Gas Turbine Generators and Auxiliaries B .Heat Recovery Steam Generations C. Feedwater and Condensate System D. Steam Turbine Generator and Auxiliaries E. Steam Turbine Condenser F. Condenser Cooling System / Cooling Tower G. Water Treatment System H.Auxiliary Cooling Water System I. Raw Water Supply System J. Effluent Treatment System K. Gas System L. Combustion Air and Exhaust Gas System M. Chemical Feed System N. Compressed Air System 0. Plant Fire Protection System P. Building Ventilation and Air Conditioning

IIV. ELECTRICAL SYSTEMS A. General B.Plant Step-up Power Transformers C. Bangkanai Switchyard - 150 kV Open Type (Air Insulated) D. Auxiliary Power System E. Black Start Capability F. DC Power System G. Uninterruptible Power Supply Systems H.Protective Relaying and Circuit Breaker Control Systems I. Synchronization J. Surge and Lighting Protection System K. Cathodic Prptection L. Site Grounding M. Equipment Grounding N. Cabling 0. Metering System P. Lighting System Q. Plant Communication SystemsR. Fire and Gas Protection and Detection Systems S. Transmission Line T. Emergency Power

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V. CONTROL SYSTEM (DCS)VI. CIVIL ENGINEERING AND BUILDING WORKSVII. MAJOR EQUIPMENT DESIGN DATAVIII. PLANT MAJOR DESIGN CONDITIONSIX . PROJECT CODES AND STANDARDSX. PLN DESIGN REVIEWXI. DESIGN/REFERENCE DRAWINGS AND SPECIFICATIONS PROVIDED BY PLN XII. REFERENCE DRAWINGS AND EXHIBITS PROVIDED BY SELLER

PART B ADDITIONAL UNIT AND SPECIAL FACILITIES EXTENSION I. GENERAL II. DEFINITIONS III. MECHANICAL PLANT

A. Gas Turbine Generators and Auxiliaries B. Water Treatment System C. Raw Water Supply System D. Effluent Treatment System E. Gas SystemF. Combustion Air and Exhaust Gas System G. Compressed Air System H. Plant Fire Protection System I. Building Ventilation and Air Conditioning

IV. ELECTRICAL SYSTEMS A. General B. Step-up Power Transformers C. Bangkanai Switchyard Extension - 150 kV Open Type (Air Insulated) D. Auxiliary Power System E. Start Up F. DC Power Systems G. Uninterruptible Power Supply (UPS) Systems H. Protective Relaying and Circuit Breaker Control Systems I. Synchronization J. Surge and Lightning Protection System K. Cathodic Protection L. Site Grounding M. Equipment Grounding N. Cabling 0. Metering System P. Lighting System

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Q. Communication Systems R. Fire and Gas Protection and Detection Systems S. [Intentionally Left Blank] T. Emergency Power

V. DISTRIBUTED CONTROL SYSTEM (DOS) VI. CIVIL ENGINEERING AND BUILDING WORKSVII. MAJOR EQUIPMENT DESIGN DATAVIII. MAJOR DESIGN CONDITIONS IX. PROJECT CODES AND STANDARDSX. PLN DESIGN REVIEW XI. DESIGN / REFERENCE DRAWINGS AND SPECIFICATIONS PROVIDED BY PLN XII. REFERENCE DRAWINGS AND EXHIBITS PROVIDED BY SELLER

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APPENDIX APROJECT DESCRIPTION AND DESIGN CONDITIONS

PART A OPEN CYCLE PLANT, COMBINED CYCLE PLANT AND COMPLETED SPECIAL FACILITIES

This Appendix A Part A applies only to the Completed Project, comprising the Completed Special Facilities, the Open Cycle Plant and the Combined Cycle Plant, and all references herein to the Project, Special Facilities Extension and Plant shall be read accordingly.

I. GENERAL The Project, also known as the Bangkanai Private Power Project, is a gas fired combined cycle electric generating station located at Bangkanai, Central Kalimantan, Indonesia. The Plant is designed to deliver nominal net design capacity of 2x40 MW in open cycle prior to Commercial Operation Date, and 120MW in combined cycle on and after Commercial Operation Date to the PLN Grid System. The Plant will be designed, constructed, tested, commissioned, owned, operated and maintained by the Seller. The Project also encompasses the design, construction, testing and commissioning by the Seller of the Special Facilities described herein, which Special Facilities will be owned, operated and maintained by PLN after Taking Over in accordance with Appendix J. The total land areas and rights of way required for the Project is approximately 15 hectares, as described in Appendix T.

II. DEFINITIONS All capitalized terms shall have the meanings given to them in the Power Purchase Agreement (the "Agreement") to which this Appendix A is attached, except as otherwise defined herein. The capitalized terms set forth below shall have the following meanings: "Construction Interface(s)" shall mean the physical tie-in(s) between PLN Grid System and both the Completed Project and Expansion Project, as defined in Appendix I. "Electrical Interconnection Facilities" shall mean certain electrical facilities (including associated protection devices if any) to be designed, constructed, tested, commissioned by Seller and turned over to PLN in accordance with "Taking-Over" procedures as defined in Appendix J. Upon Taking-Over by PLN, PLN shall own, operate and maintain the Electrical Interconnection Facilities. "Interconnection Point(s)" shall mean the physical point(s) of on-going operational interconnection and jurisdictional boundary between the Plant and PLN Grid System. Interconnection Point(s) are further described in Appendix I.

"Plant" shall mean:

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(i) where used in a context with reference to a period prior to the Commercial Operation Date, the two gas turbine and generator Units and the associated plant and equipment installed at the Site (the "Open Cycle Plant")

(ii) where used in a context with reference to a period on or after the Commercial Operation Date through to the Additional Unit Commission Date, the two gas turbine and generator Units, the two heat recovery steam generating Units, the single steam turbine and generator Unit and the associated plant and equipment installed at the Site (the "Combined Cycle Plant") and

" Bangkanai Switchyard" shall mean:

(i) where used in a context with reference to a period prior to the Taking-Over of the Special Facilities Extension in accordance with the "Taking-Over" procedures in Appendix J, the open type 150 kV switchyard located adjacent to the Combined Cycle Plant, to be taken over in accordance with “Taking Our” procedure in appendix J

"Special Facilities" shall mean:

(i) where used in any other context, the Special Facilities Extension to be designed, financed, constructed, tested and commissioned by Seller and to be taken over in accordance with the "Taking-Over" procedures io Appendix J, as further described in Part B of Appendix I (the "Special Facilities Extension").

Upon Taking-Over by PLN, PLN shall own, operate and maintain the Special Facilities. For the purposes of testing and Taking-Over of the Completed Special Facilities, the following shall be the "discrete elements" referenced in Appendix I and Appendix J:

i) Completed Interconnection Point(s); ii) Completed Electrical Interconnection Facilities; iii) Completed Bangkanai Switchyard; iv) Transmission Line; and v) Completed Construction Interfaces.

"Transmission Line" shall mean the 150 kV double circuit, single Zebra conductors and earthwire suspended on steel towers, extending from the Bangkanai Switchyard to the Buntok Substation. The Transmission Line is further describe in Section IV.S and in Appendix I.

III. MECHANICAL PLANT A Gas Turbine Generators and Auxiliaries

The gas turbine unit is a well proven heavy duty unit developed for industrial and utility 50 Hz power generation applications. The gas turbine generator package is completely engineered with integrated systems that includes controls, auxiliaries, ducting and silencing. The gas turbine is designed to attain high availability levels coupled with fast maintenance overhaul requirements and high reliability. To achieve the required operating pressure, the turbine is arranged to drive a compressor as well as the intended load, in this case an electrical generator. The compressor is multi stage

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axial flow designed developed to minimize the work done in compression and maximize available power to the generator.In an aerodynamic design it is essential that stalling should be avoided so that damage does not occur. The varying air flow through the compressor when increasing speed during starting is controlled by inlet guide vanes. There is sufficient margin between operating condition at constant speed and conditions resulting in stall that the selected turbines do not experience stall phenomena during operation. The standard natural gas combustion equipment has the characteristics to ensure stable combustion over the full range of gas flows from ignition to full power. It will perform within the required range of emissions and have an acceptable life. The turbines are characterized as being of high energy per stage design, which have the advantage of a lower bucket temperature allowing higher firing temperatures to the turbine inlet. The gas turbine is modularised to speed erection and to ensure maximum retention of works quality. Modules are weather proof and noise attenuated. Attenuation is provided to achieve the boundary and personnel safety noise levels on the site. Modular skids are provided for ancillary services. Lubricating oil cooling is provided. Load/speed control and turbine supervisory functions are provided by the proprietary control system that incorporates multiple redundant supervisory functions and on-line testing of critical trip functions. (Refer further to Section V.) The gas turbine generators are designed for operation under the site conditions. Each generator is provided with the complete complement of neutral and line side facilities, protection relaying transformers, brushless excitation and AVR, surge arrestors, as well as the generator voltage circuit breaker, all housed in weatherproof containers immediately adjacent to the machine. Electrical integrity of the important generator zone is thereby maximised. Each gas turbine exhaust system includes a full gas bypass with stacks.

B. Heat Recovery Steam Generators The Heat Recovery Steam Generator (HRSG) is specifically designed to operate in conjunction with the gas turbine, with performance matched to the gas turbine operating characteristics to achieve highest Plant efficiency. It has been designed as a fully integrated system consisting of all required ductwork and boiler components including pressure parts associated support, casings, insulation, valves and mounting together with appropriate control valves and equipment. The design allows:

• Fast start-up and shutdown • Flexibility of operation • High reliability and availability

The HRSG is a natural circulation type with horizontal gas flow and vertical fin tubes in all sections. The HRSG fabrication is undertaken in a number of discrete prefabricated modules to maximize the quality of workmanship and minimize the time and cost of field installation. The HRSG evaporator sections include large steam drums to ensure proper steam purity and to manage during start-up and operating transients, any tendency to surge. Downcomers are configured for proper natural circulation. Heat transfer surface is of the extended surface type

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consisting of spiral finning continuously welded to the tubes. All pressure parts are fully drainable and ventable for filling and proper operation. The ductwork and boiler casing are designed using proven methods suited for positive-pressure heat recovery boilers to maintain low outer face temperatures and low total thermal expansion. A system of platforms, stairways and ladders are included for access to valves and instrumentation. Access for inspection and maintenance is provided by suitably located horizontal access doors in the casing and ductwork. A complete set of instrument connections for monitoring water, steam, gas pressures, and temperatures will be provided.

C. Feedwater and Condensate System A feedwater / condensate system of 2 x 100% capacity delivers the feedwater to both HRSG's. The pumps are horizontal, multi-stage type with pressure controls automatically starting the standby pump on falling feedwater pressure. They are serviced by a forced lubrication system and include leak-off systems for protection on low flow. Condensate is also used for the following purposes:

• Steam turbine exhaust hood spray • Chemical injection solution tanks • By-pass line desuperheaters

The required minimum flow through the condensate pump and gland steam condenser is automatically provided via a flow control valve to recirculate condensate.

D. Steam Turbine Generator And Auxiliaries The steam turbine is of axial exhaust design that minimizes turbine room civil costs. A high efficiency is achieved by use of high performance nozzle profiles. The turbine is designed with operational recognition flexibility. The requirement of rapid start-up is assisted by provision of independent steam bypass valves on each GT/HRSG unit with combined capability to pass 100% nominal turbine steam flow. This arrangement allows effective matching of steam and turbine metal temperature on start-up as well as providing maximum flexibility in operation. Ancillary plant packages are provided for lubricating oil and control fluid. Critical services are provided with backup DC drives providing ultimate protection against emergency shutdown. Maximum cycle efficiency is maintained through inclusion of a gland steam condenser. As with the gas turbine plant, turbine control is provided by the proprietary control system. The steam turbine generator is selected as a closed air water cooled design. Heat is rejected through the cooling tower system. Again the generator is provided with the complete complement of neutral and line side facilities, protection relaying transformers, brushless excitation and AVR, surge arrestors. as well as the generator voltage circuit breaker, all housed in weatherproof containers. Electrical integrity of the important generator zone is again maximised.

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E. Steam Turbine Condenser The turbine condenser is a single shell, two-pass waterbox, shell and tube design. The condenser maintains .a low exhaust pressure on the turbine as well as being a sink for bypass steam on steam turbine start-up or load rejection, and a receiver for low pressure steam and condensate drains. Condenser hotwell level is automatically controlled by a split-range control. Excess condensate is delivered a storage tank while make-up condensate is delivered to the condenser on low level. Condensate deaeration is carried out in the condenser. The condenser air removal system creates and maintains vacuum in the shell side of the main condenser by removing air and non-condensible gases. The system consists of multiple steam jet-air ejectors. Non-condensible gases flow from the main condenser to the air ejector packages during normal operation. During start-up, a hogging is operated in parallel to prepare the condenser for service most rapidly.

F. Condenser Cooling System / Cooling Tower The circulating water system supplies cooling water to the main condenser and to the auxiliary cooling water system. Cooling water is supplied by two circulating water pumps. The circulating water is transported from the discharge header by buried piping to the condenser inlet waterboxes. The pump outlet pipes and the condenser inlet and outlet waterbox pipes are each fitted with expansion joints and motorized butterfly isolation valves. The condenser outlet waterbox pipes discharge into buried piping which returns the circulating cooling water to the cooling tower. A counterflow mechanical draft evaporative cooling tower system is provided. Cooling tower frame and casing construction material is timber and concrete. The filling will be polyvinyl chloride fill pack with stainless steel support. Water distribution in the cooling tower is by low pressure spray. Cooled water from the tower is returned to a concrete basin and is led to the cooling water pump suction via trash screens. The tower is divided into separate cells to facilitate routine maintenance.

G. Water Treatment System Water treatment for the Plant is provided for the following purposes:

• Compensate for water chemicals and suspended solids likely to cause degradation of heat exchanger performance • Control algae growth in water storage and cooling tower • Provide high quality water for steam cycle make-up • Provide potable water for the power plant use, and associated housing settlement.

Details of the principle processes are as follow: Portable Water After solids filtration, the potable water stream will be passed through activated carbon filters to remove organic contaminants. Chlorination of the Potable Water Supply will also be included to disinfect the supply and the storage and reticulation system. This process will be based on sodium hypochlorite injection. Demineralisation Treatment A demineralisation plant will produce high priority de-ionised water suitable for boiler feedwater makeup.

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Two trains incorporating activated carbon filter, cation vessel, degasser anion vessel and polishing mixed bed vessel will supply the demineralised water storage tank. Each train will be fully instrumented with additional common Conductivity metering on the supply line to the storage tank to safeguard against slippage of acid and caustic regenerants.

The Plant will be fully automatic in operation with manual override facilities.

Cooling Water Treatment

Both the condenser and auxiliary cooling water systems will be provided with chemical treatment at the discharge side of the respective pumps. Chemical dosing will include for sodium hypochlorite, anti scalant and descalant additions system design will also enable a small proportion to the recirculations water to be passed via sand filters to ensure minimum deposition of suspended matter in the cooling circuits.

H. Auxiliary Cooling Water SystemThe auxiliary cooling water system is serviced from the cooling water pumps. Auxiliary cooling water is piped to a number of heat exchangers:

• Steam turbine lube oil coolers and hydraulic fluid coolers. • Steam turbine generator • Steam/water sample coolers

Heat exchanger material in selected for use with water of cooling tower quality to ensure reliable service. Auxiliary cooling water is returned to the cooling tower via the circulating water return piping.

I. Raw Water Supply System The water requirements for the Plant will be provided from the Cenranae river. Two 100% pumps will be located on a concrete intake structure. The intake structure will incorporate solids removal devices to ensure heat exchanger and cooling tower performance is not affected by any water impurities. The cooling tower make up water consumes most of the water requirement as it is proposed to required for the Plant.

J. Effluent Treatment System Waste water treatment wilLbe provided for discharges from the Plant and equipment, and the site, to meet the regulations. The discharges to be treated will include:

• Chemical storage area • Plant floor drainage • Effluent from water treatment/purification plant • Effluents from Laboratory, • Steam generator blowdown • Domestic sewage • Oily waste streams• Metal in water treatment

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Treatment will include provision of necessary holding tanks to allow chemical neutralization and settlement before discharge.

Effluent Treatment System

This plant is basically a solids separation basin with the specific intention of controlling the level of solids return to the river. Effluent water will be discharges from the separation basin to the drainage system leading to the river.

Domestic Sewage Treatment

A sewage treatment plant will be provided which will have the required plant treatment capacity of raw sewage to meet the maximum acceptable "Bio-Chemical Oxygen Demand-5 day test" (BOo) content.

Oily Waste Management

Areas and equipment with the potential for oil in their waste stream and will have their drains routed through a oil/water separator where the oil will be separated out and held for disposal while the water is discharged to the river outlet. This oil as well as the waste fuel oil, lube oil and water wash effluent captured in holding tanks will be disposed of off-site. Areas outside the buildings with the potential for oil in the waste stream include the transformer zone and distillate fuel oil storage tanks. These areas will have containment dikes. There will be various normally closed valves associated with the oily water system. Prior to opening these valves, the area will be checked to ascertain there has not been a spill. The oil/water separator is not designed to contain major oil spills, which must be treated separately.

K. Gas System The gas processing system will deliver gas to the individual gas turbines at the required turbine conditions. The gas scrubbers will come complete with a liquid level control system to automatically maintain a safe level of accumulated liquid in the scrubber. Accurate station gas metering is provided in this installation. A final strainer filter will be supplied for each gas turbine to remove particulate matter thereby providing a clean gas to the turbine combustors. Metering will be provided to allow a comparative measure of gas consumption to each gas turbine. Gas receival equipment is part of the gas suppliers scope. Gas will be delivered at the required condition of temperature, pressure and composition for the power Plant.

L. Combustion Air and Exhaust Gas System Each gas turbine unit's combustion air is taken at high level and the system provides filtered air to the gas turbine compressor inlet.

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The filter system consists of rain hoods, filter elements, service platforms with access ladder for maintenance. Downstream of the filtration system is mounted an in duct parallel baffle absorbent silencer. The gas turbine exhaust is ducted to the HRSG inlet. The HRSG ducting comprising the inlet transition duct, outlet transition duct and stack, are suitably stiffened on the outside by steel angle or channel sections. Outlet stack height is compatible with environmental need. Gas sampling ports are provided in the stack for emission monitoring.

M. Chemical Feed System The chemical feed system consists of separate subsystems which serve the HRSG and condensate system and provide for phosphate injection, oxygen scavenger injection and amine injection. The subsystems will consist of solution tanks with adjustable metering pumps for each HRSG and condensate injection point. The cooling towers will also receive chemical dosing.

N. Compressed Air System The compressed air system is comprised of the instrument air system and the service air system. Instrument air is required for air-operated valves and instruments in the Plant while service air is used for power tools and other power services. The supply of instrument and service air is directed to an air receiver. From the air receiver the air is directed to the instrument air system and also to the service air system distribution network. Service air connections are provided from the instrument air header at various locations throughout the Plant. Air is blocked from the service air distribution connection until instrument air header pressure is high enough to satisfy the instrument air system. This ensures that the instrument air system requirements will always be satisfied prior to the service air requirements. Compressed air passes through filters and a dryer prior to entering the instrument air distribution system. One dryer is operating while the other is regenerating.

O. Plant Fire Protection System A self-contained fire fighting system is provided for the Plant. It draws on water reserves in the cooling tower basin for fire fighting. Electric motor driven and diesel driven main fire pumps are provided. A jockey pump (general services pump) is provided to maintain pressure in the firewater lines when the main pumps are not in operation. The Plant firewater main is a buried system that divides the Plant area in multiple fire loops. Fire hydrants with hose houses are located around the Plant for external fire fighting coverage. Deluge systems are provided for fire protection of the outdoor transformers. Sprinkler systems and hose racks are provided in buildings and Plant areas. Fire extinguishers are located throughout the Plant as required by local fire codes. Gas turbine modules contain integral CO2 fire protection systems as necessary.

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P. Building Ventilation And Air Conditioning The control room administration quarters and other selected areas are climate controlled with air conditioning and/or ventilation. Service plant areas are ventilated as required to maintain acceptable ambient conditions for Plant and operational staff.

IV. ELECTRICAL SYSTEMS A. General

The Plant is designed to supply power to the 150 kV PLN Grid System in Central Kalimantan The station electrical system design inherently contains a number of major electrical equipment redundancies in order to reduce and mitigate the effects of undesirable outages which may be caused by out-of-service status of auxiliary equipment. The Plant is designed to derive auxiliary power supply for each unit by import from the 150 kV system through the generator step-up transformers. Auxiliary power is therefore taken from a common point and changeover between an auxiliary supply and unit transformer is not required following synchronization of the generator. This simplifies station operation and improves security. A black start capability is an integral feature to allow re-start of a gas turbine generator set following the loss of start-up power supply from the PLN Grid System. The generator is utilized to provide an emergency power to Plant systems requiring an emergency power source in the event that the in-Plant and off-Plant generation sources are both lost. It will also secure supply to the 150 kV switchyard services. Metering Systems are provided and installed to measure and record the power exchanges between the PLN Grid System and the Seller's power generation facility. Fibre optic type circuits or alternative system for protective, data, and communication channels will be utilized as required between the Plant and the 150 kV switchyard facilities. The electrical power generated by the Plant will be made available to PLN's 150 kV power network through the interconnection Point(s). The generator circuit breaker on the step-up power transformer low voltage side, owned and operated by the.Seller, will be used as the synchronizing breaker for each turbine generator unit. The transformer feeder 150 kV switchyard circuit breakers will not be used for direct synchronizing with the PLN Grid System. The Plant's generator circuit breakers will also be used to isolate a generating Unit from PLN Grid System under normal shut-down conditions. In the event of a PLN emergency condition on the PLN Grid System, the transformer feeder 150 kV switchyard circuit breakers under either PLN or Sellers control, may be utilized to isolate the Plant and maintain the gas turbine generators at speed ready for immediate resynchronisation.

B. Plant Step-Up Power Transformers Step-up transformers will be 3 phase, single oil-filled units, rated to match or exceed gas turbine base load rating under all ambient conditions. At low ambient temperatures natural air cooling will suffice, while under higher ambient conditions, forced ventilation fans will automatically be activated to hold oil temperatures within acceptable limits. These transformers are also equipped with on load tap changing facilities to permit system reactive flow control while maintaining generator voltage within the rated limits.

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The turbine generators are bus connected to their associated generator circuit breaker (GCB) and thereafter cable connected to the 150 kV generator step-up transformer. The transformer output is connected to the 150 kV switchyard by overhead aerial connections. Each generator main step-up transformer will be equipped with a high side circuit breaker, disconnecting switches and grounding switches for protection and local control by PLN.

C. Bangkanai Switchyard - 150 kV Open Type (Air Insulated) Output from the generator transformers is connected via 150 kV circuit breakers of an SF6 design to the switchyard buses. The switchyard is constructed in a conventional double bus configuration. Switchyard relaying and control systems will be accommodated in a relay room located in the switchyard. Energy metering equipment is provided to record energy export/import through the generator step-up transformer CBs. Space provision for two additional bays is included within the Bangkanai Switchyard perimeter for possible future PLN interconnection requirements.

D. Auxiliary Power System Supply from the generator terminals at 11.5 kV 50 Hz is transformed to the supply voltages appropriate to the respective unit auxiliary loads. For the Plant, the major drives are connected to the motor control centres utilising vacuum or SF6 contactors, Two transformation stages are provided for this Plant. Supply to essential station auxiliaries is also drawn from the auxiliary buses. In the event of total loss of auxiliary supply, these buses are secured by the diesel generator (see Section F). The Plant is designed with its own independent medium and low voltage switchgear.

E. Black Start Capability A black start capability is an integral feature designed to allow re-start of a gas turbine generator set following the loss of start-up supplies from the PLN Grid System. As the facility is an integral part of the Plant, all gas turbines can be restarted and held ready for resynchronisation and connection.

F. DC Power Systems Centrally located DC systems are included in the power plant. A dedicated 125 V DC system is contained within each gas turbine packaged plant. A common 125 V DC system will power the plant steam turbine DC loads and the station control system. The plant electrical relay protection will be based exclusively on the use of DC power for tripping. Redundancy is provided in the battery charging facility.

G. Uninterruptible Power Supply Systems The Plant is provided with a UPS system to provide continuous AC power to essential control and instrumentation AC buses. The UPS complement is provided with an independent supply sources and a DC supply source from the DC power system. Static bypasses provide operating and maintenance flexibility.

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H. Protective Relaying and Circuit Breaker Control Systems 150 kV switchyard protective relaying systems will accord with PLN standards and have been configured on a mix of "Main and Main" as well as "Main and Standby" arrangements. In any event duplicate visibility exists for all anticipated fault conditions. Such duplicate visibility is extended for fault conditions throughout the generator transformer and generator zones. Throughout the power station auxiliary system, protection systems will be developed around coordinated over current and earth fault systems with reliance on fuse and thermal relaying at the lowest levels. High voltage motors will be provided multi-function solid state motor protection relaying. Control locations for circuit breakers (CBs) are proposed as follows –

• Generator transformer 150 kV CBs. • All lower voltage systems - Power Plant only. • All 150 kV isolators - PLN control.

All CBs under power Plant control will be controlled through the station DCS. Auxiliary system CBs will in general also be locally manually operable for ultimate supply security. Generator voltage CBs will be excluded from local operation.

I. Synchronization The Plant's generators are designed to be synchronized with PLN's 150 kV Grid System across Seller's owned and operated generator voltage circuit breakers located on the low side of the main step-up power transformers. Upon start up of any unit, after the turbine generator reaches proper voltage and frequency, it will be automatically synchronized to the system by closing the respective GCB. Synchronizing will include for both a synch - verifier and sync-check function. Manual synchronising with sync-check will be available as a standby in the event of auto-sync failure. The Plant auxiliary power system is provided with fast transfer capability and utilises sync-check devices as necessary.

J. Surge and Lightning Protection System Earthing switches and surge diverters are installed on the 150 kV installation at the appropriate locations for safety and impulse voltage control. All equipment on the LV side of the step-up transformer will be co-ordinated in BIL selection with generator terminal surge diverters fitted as required. All high structures will be designed to lightning codes and earthing grids designed for adequate impulse grounding.

K. Cathodic Protection The cathodic protection system, based on soils resistivity data, will be designed and constructed consistent with Good Utility Practice. Pipelines both on and off-site will include appropriate features.

L. Site Grounding IEEE-80 recommendations and ANSI/IEEE 665 or equivalent international standards are used to determine grounding system requirements for the gas turbines, the Special Facilities, the Plant boundary fence, steel structures, buildings and the ground grid interconnecting PLN's 150 kV

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overhead line grounding conductors. The entire ground grid system exclusively utilizes copper conductors with exothermic connections for in-ground connections.

M. Equipment Grounding Equipment grounding is based on full compliance with either ANSI/IEEE- 142 AS 3000 or equivalent international standard.

N. Cabling Cabling and raceway application for the Plant and the Special Facilities, will have fire retardant properties to International Standards in accordance with Good Utility Practice. Control and signal cabling between the power Plant and Special Facilities will use fibre optic or alternative system isolation interfacing at the switchyard relay room

O. Metering System Import/export billing meters are supplied and installed to measure the power exchanges through the generator step-up transformer 150 kV feeder CBs. The billing meters and associated equipment for each metering point are installed by the Seller. The Metering System is sealed by PLN. The billing Metering System is accessible by electronic connection to both the Seller and PLN for information only. These meters are utilized to record all major power transfer. The metering equipment is digital-based. Single channel solid state uni-directional energy meters will summate for billing purposes the low level power supply to the switchyard relay room from the power station auxiliary system.

P. Lighting System Plant lighting for all indoor and outdoor facilities including access and maintenance roads is provided in accordance with applicable illumination standards and Good Utility Practice. Outdoor lighting will be sodium or metal-halide type and will provide illumination in areas of normal personnel traffic, such as:

• Building exteriors • Transformer areas • Walkways & stairs • Roadways

Indoor lighting will be high pressure sodium or metal-halide type in high bay building areas and fluorescent type in all other areas. Emergency lighting of the wall mounted battery pack type will provide adequate levels of illumination for all building exit routes.

Q. Plant Communication Systems An in-house Plant communication system is provided to link remote facilities and systems to the main control room and other critical offices within the Plant. Normal communications with outside facilities including PLN Dispatch Center is provided via a secure telephone link. A microwave link or a telephone cable extending to the Plant battery limit at which point PLN will continue the circuits to their ultimate destination. In addition, subject to clarification of specific PLN requirements and equipment form and location, it is intended to interconnect with PLN's SCADA system via instrument cable to provide alarm, monitoring, communication

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and telemetering of the Bangkanai Switchyard and key power Plant data. PLN will be responsible for all off-site SCADA communication circuits and wiring.

R. Fire and Gas Protection and Detection Systems A complete fire and gas detection and fire fighting system covering essential areas, rooms and plant containing combustible material is provided in accordance with applicable standards, regulations and Good Utility Practice. The system includes a control panel in the central control room, which monitors the status of remote zones. These remote zones are located in designated areas throughout the facility and embrace various detectors, signal boxes and fire fighting flow switches. Linked with each zone and the main control panel are horns to warn Plant personnel.

S. Transmission Line The Transmission Line will comprise of 150 kV double circuit, single Zebra conductors and earthwire suspended on steel towers. The Transmission Line will extend from the Bangkanai Switchyard to the Buntok Substation, a distance of approximately ...... km. The scope of work for the Transmission Line will include design, manufacture, supply, testing, insurance, packing for export, shipment, delivery to site, detailed survey and soil investigation, plotting, pegging, setting out, complete erection, foundations, stringing, commissioning for subsequent Taking Over by PLN.

T. Emergency Power In the event of a station collapse and separation from external supply, the DC systems will immediately secure critical functions. An emergency generator is provided to in turn enable securing of the battery chargers and other AC loads for the safe shutdown of the station and the holding of the station in readiness for restart. The emergency generator capacity is sufficient to service the gas turbines and steam turbine emergency demands plus essential services associated with the control centre and associated systems.

V. CONTROL SYSTEM (DCS) A common Plant control system is designed to control the multiple machine combined-cycle power Plant. The primary control location is a central control room. This central control room contains an operator console, printers, engineering workstation, and other auxiliary equipment. The DCS provides remote control functions to the operators of the Plant equipment either directly from the DCS control processors, or indirectly through serial data links or hardwired points to remotely located control packages. The DOS equipment provides the operator with graphic displays which depict the arrangement of the Plant. All DCS control and supervision of Plant operation will be screen or keyboard based. Selected critical functions are hardwired between the control room and the Plant. A separate DCS alarm display presents alarms in a custom graphic display format with priorization scheme for easy recognition of critical alarms. Cabinet housing the DCS processing units, communication modules, and input and output modules are located in an adjoining control equipment room or remotely in environmentally

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controlled shelters. Redundant DOS communication buses connect the processing units to the operator stations and to field mounted processing units servicing peripheral Plant systems. Limited preset operations are carried out in the field by a roving operator, from local control panels or the motor control center. The operator in the central control room confirms that all equipment is ready to start. Field operators monitor opening and closing of the HRSG and steam turbine drain valves and start up of other plant as necessary, to support the automated start-up and shutdown of the steam turbine unit. The DOS system has the capability to manage and supervise control of both the gas and steam turbines from the start-up command to full speed, synchronize the generator and load the turbine-generator to the operator designated load. Actual machine control is exercised by the individual unit control system, this system also providing the ultimate machine protection functions. Protection logic provides for multiple redundant monitoring and/or actioning functions as appropriate. Further loading of the gas turbine is dependent on operational decisions to continue to load the gas turbine and compatibility with the process of warming-up the HRSG and achieving required steam temperatures. The steam turbine is loaded by the operator as the temperature differential between the steam and the turbine shell temperatures allow and, in accordance with a verified and predetermined loading rate set by the operator. After the Plant has reached the operator determined load, the unit operates automatically without operator direct attention or ongoing adjustment. The combined-cycle unit automatically responds to changes in load requested by the operator with DOS functions allocating load changes between available machines. The DOS to varying degrees indirectly controls and/or monitors the following local control packages by transmitting starting, stopping, and other commands, and by receiving status and alarm information. The equipment to be serviced includes:

• HRSG plant• Cooling water and cooling tower systems• Condensate and feedwater plant • Water treatment Systems• Compressed air and service water system• River water plant • Other minor plant systems including HVAC

The necessary portable apparatus for emission monitoring, to meet the requirements of the regulations, will be supplied. A data acquisitions system will provide emissions reports. All gauge indications will-be consistent with the Imperial system of measurement, with the exception of the interface systems in the switchyard which will be consistent with the Metric system.

VI. CIVIL ENGINEERING AND BUILDING WORKS The Site, which is located approximately 10 km to the southeast of Bangkanai in Central Kalimantan is currently used for small scale agriculture. The Geotechnical information on the site was based on the preliminary site selection study report. Additional investigations will be performed in the final civil design development stage of the Project.

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The Site will be cleared of vegetation as part of the overall Site preparation, a survey of the existing ground will be performed to establish the Site boundaries and Site datum prior to commencement of the Site levelling operation. The Site grade will be established to the required level by cutting and filling with compacted earth. All equipment and facilities will be supported on appropriately designed foundations. All custom built structures will be designed as pin connected braced steel frames. All structural steel will be designed, detailed and fabricated in accordance with international standards. A lined gravel pit will be provided for the transformer and Switchyard equipment with concrete curbs around the perimeter. The volume of the pit will be sufficient to retain the spillage of the total volume of the oil of the transformer plus 30 cm (one foot) of freeboard. Concrete dikes with corrosion resistant coatings will be provided for the acid and caustic storage tanks. The dikes will be sized to contain a volume equal to the total volume of the largest tank enclosed.

ARCHITECTURAL CONSIDERATIONS Turbine Building The building will house the steam turbine generator. The enclosure will meet the acoustic design requirements. The roof will be sloped and drained by gutters and downspouts. Miscellaneous Buildings The Central Control, Administration Building and Switchyard Relay Room will be a manufactured or custom designed building. The following buildings will be manufactured metal system type buildings:

• Water Treatment Building • Maintenance Building

The Guard House will be a manufactured metal system type completely pre-engineered building. The architectural considerations and site landscaping will be in keeping with the overall amenity of the area.FencingAll corners of the Plant area will be marked and the property will be fenced-in. The perimeter security fence will be approximately 2.5 m high zinc coated steel mesh, with three (3) strands of barbed wire on the top. The security fencing will have emergency exists, with remotely operated and powered security gates and lighting. The river water extraction pumping station will be contained within its own perimeter security fencing with lockable gates. The fence materials will be the same as those for the Plant fence system. Roads An access road will be constructed (upgrading an existing path) to a suitable quality. Construction of this access road will be made without impacting on the adjoining paddy fields. Plant service roads will be provided to give adequate access to all plant and buildings on the Site. The Plant service roads will be constructed between raised curbs and graded to drain into gullies connected to the surface water drainage system. The Plant service roads and parking areas will be paved with asphaltic concrete. For transportation of plant and equipment purposes, road improvements will be provided where necessary along the route from the unloading port to the Site.

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VII MAJOR EQUIPMENT DESIGN DATA Seller shall confirm in writing to PLN not later than two months following the date of this Agreement the selection of Plant Type.

Nett Plant Output (Nominal) Plant A Prior to CommercialOperation Date 2 x 40 MW On or after Commercial Operation Date 120 MW

Gas TurbineNumber 2Rotational Speed — GT 6200 rpmRotational Speed — Generator 3000 rpmFuel Natural GasBy-Pass Stack Height 20 meters

HRSGNumber 2Type Single pressureSteam Temperature 513°C a Steam Pressure (HP) 45.0 barExhaust Stack Height 30 meters

Steam TurbineNumber 1 Rotational Speed 3000 rpmType Single-flow

dual pressure Straight condensing

Gas Turbine – GeneratorRating 40.00 MW Frequency 50 Hz Power Factor 0.85 lagging Volatage 11.5 kV Generator Cooling TEWAC Stator Cooling Air

Steam Turbine - Generator Rating 40.00 MW Frequency 50 Hz Power Factor 0.85 lagging Voltage 11.5 kV Generator Cooling TEWAC Stator Cooling Air

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Main Step-Up Transformers - GT (2 off) Phase 3 Number of Winding Two Voltage 150 / 11.5kV Frequency 50 Hz Type ONAN / ONAF Rating (Design) 60 MVA BIL Rating H-750, L-95 Lightning Arrestor Rating 150 kV High Side On-Load Tap Charger Automatic

Main Step-Up Transformer - ST (1 off) Phase 3 Number of Winding Two Voltage 150 / 11.5 kV Frequency 50 Hz Type ONAN / ONAFRating (Design) 70 MVA BIL Rating H-750, L-95 Lightning Arrestor Rating 150 kV High Side On-Load Tap Charger Automatic

Unit Auxiliary Transformers Plant Phase Number of Winding Voltage Frequency Type Rating BIL Rating

Phase Number of Winding Voltage Frequency Type Rating BIL Rating

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6.6.kV (2 off) 3 Two 11.5 / 6.6 kV 50 Hz ONAN 5 MVA H-95 kV, L-75 kV

2.1kV (1 off) 3 Two 11.5 kV / 2.1 Kv 50 Hz ONAN 2.6 MVA H-95 kV

Low Voltage Transformers Plant PhaseNumber of Winding Voltage Frequency Type Rating BIL Rating

Phase Number of Winding Voltage FrequencyType Rating BIL Rating

Bangkanai SwitchyardRating Breaker Scheme BIL Rating Isolator/CB Capacity Continuous Rating Interrupting Rating Transmission Line Conductor TypeNumber of. Conductor Size Earthwires Insulator Sets Suspension Structures Uninterruptible Power Supply System Type Rating (AC System) Rating (DC System) Battery Rating

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400 V (2 off) 3 Two 6.6 kV / 400 V 50 Hz ONAN 2.5 MVA H-75 kV, L-5 kV

450 V (1 off) 3 Two 11.5 kV/450 V 50 Hz ONAN 1.25 MVA H-75 kV

150 kV (nominal) Double busbar, single CB(SF6) 750 kV2000 A 2000 A31.5 kA

Zebra 6 428/56mm2 Skunk (2) Single Suspension StringSteel Towers

Static Load + 15% Matched to AC rating 2 hours

Feedwater / Condensate System Boiler feedwater Pumps Booster Pumps

Condensate Make-Up Water System Sources Treatment Nominal Capacity Storage Capacity

Circulating Water System Temperature Rise Circ Water Intake Circ Water Pumps Nominal Capacity (max.) Water Treatment

Condenser System Type Design Tube Material

Steam Jet Air Evacuation System Two Stage Service Ejector Start-up ejector for Start-up and as backup of service ejector

Condensate Flow Condensate Pumps (Feed Pumps). included in Boiler

Raw Water Supply Sources Treatment Capacity Pumps

Black Start Generator System Diesel Generators Size Voltage (nominal)

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2 x 100% pumps 2 x 100% pumps

Demin. water system Two train demin. system 5.5 m3/h (2 trains) 150 000 liters

14.5°C Cooling tower basin 2 x 50% pumps 48 000 l/min each Chlorination / Dispersants / Inhibitors

2 pass shell & tube type ABB Standards Stainless Steel, SS316 L

1 x 100%

1 x 100%

Kapuas or Teweh River Settling pit, screen/clarified 2 x 160 m3/ hour

12000 kVA 6.6 kV, 3 phase, 50 Hz Distillate / Natural Gas Fuel

VIII. PLANT MAJOR DESIGN CONDITIONS A. Finished Grade Elevation Around

the Turbine and Boiler Buildings above mean sea level: 10 m

B. Annual Air Temperature Design 28.5°C Maximum 38.0°C Minimum 15.0°C

C. Annual Relative Humidity Design 75% Maximum 100%

D. Wind Speed at Site Normal 1.5 — 5.8 m/secMaximum 25 m/sec (design)

E. Seismicity Indonesian Earthquake Zone D Earthquake coefficient z = 1 Return period T = 50 years Design ground acceleration k = 0.06

F. Electrical Maximum 3-Phase Fault at 150 kV for 250 milliseconds durations: (subject to PLN design) 31.5 kA Maximum 1 -Phase Fault at 150 kV for 250 milliseconds durations: (subject to PLN design) 31.5 kA

G. Atmospheric Pressure Design 1.000 Bar a

IX. PROJECT CODES AND STANDARDS Internationally recognized codes and standards including the following codes and standards or parts thereof (the latest editions as July 1995) will apply to the engineering, design, construction and commissioning of the Project.

A. GeneralAmerican Society of Civil EngineersAmerican Society of Testing and Materials American Society of Mechanical EngineersAmerican National Standards Institute

B. Civil/Structure and Architectural Engineering American Association of State Highway and Transportation Officials

American Concrete InstituteAmerican Institute of Steel Construction American Iron and Steel InstituteAmerican Welding Society Prestressed Concrete Institute

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Structural Steel Painting Council Indonesia Earthquake regulations ANS/ASCE 7-88 Min. Design Loads for Building & other Structures Concrete Reinforcing Steel Institute

C. Electrical Design American National Standards Institute Institute of Electrical and Electronic Engineers Insulated Power Cable Engineers Association National Fire Protection Association National Electrical Manufacturers Association National Electrical Code Illuminating Engineering Society

D. Mechanical Design American Boiler Manufacturing Association American Gas Association American Petroleum Institute American Water Works Association American National Standards Code for Pressure Piping - Power Piping American Society of Mechanical Engineers (Boiler and Unfired Pressure Vessels) Heat Exchange Institute Hydraulics Institute Instrument InstituteInstrument Society of America National Fire Protection Association Fire Fabricators Institute Tubular Exchange Manufacturers Association PLN Standard for Plant Noise

X. PLN DESIGN REVIEW

To facilitate the design, engineering, construction and testing of the Special Facilities, PLN and Seller agree to coordinate and exchange design requirements, operation philosophy, and PLN system data with respect to those facilities. Based on PLN supplied system data, Seller will be responsible for the design and implementation of Special Facilities. Sellers agrees to deliver drawings, plans and other similar design and engineering documents and specifications with respect to the Interfaces for PLN review and approval in each case prior to commencement of construction activities for such facilities. Testing procedures for the Special as required, will be subject to review and approval by PLN prior to commencement of testing. Upon receipt of any drawings, plans, testing procedures or similar documents, PLN shall have (3) weeks to review the documents and either approve them or submit to Seller PLN's comments regarding Seller's plans, which comments shall be consistent with the basic design and design criteria set forth in the volume(s) referred to in respect to the plans for such Special Facilities and shall be mutually addressed and resolved by the Parties. Failure of PLN to respond within such three week period shall be construed, for all purpose and irrevocably, as PLN s approval of the documents as submitted by SellerIn the event that the Parties cannot reach a mutual resolution with respect to PLN comments and concern regarding the design of Special Facilities within two calender weeks, such

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comments and concerns shall be referred to an expert for resolution in accordance with the provisions of Section 18.2 of this Agreement. Seller agrees to submit design drawings, plans, specifications and other design documents to PLN in relation to Special Facilities.

XI. DESIGN / REFERENCE DRAWINGS AND SPECIFICATIONS PROVIDED BY PLN. Seller shall use and be entitled to reasonably rely on the information as provided by PLN Design Drawings and Specifications. The Special Facilities shall be developed in accordance with such drawings and specification.

XII. REFERENCE DRAWINGS AND EXHIBITS PROVIDED BY SELLER Seller has hereby provided certain drawings and exhibits to illustrate the Project description and design conditions. Such drawings and exhibits, attached to this Appendix-A, are provided for "information only". Reference Exhibits Provided by Seller

• Site Location Exhibit A - 1 • Typical Plant Layout Exhibit A - 2 • Proposed Flow Diagram Exhibit A – 3

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